SB2026081404 - Gentoo update for Apache HTTPD



SB2026081404 - Gentoo update for Apache HTTPD

Published: August 14, 2026

Security Bulletin ID SB2026081404
CSH Severity
High
Patch available
YES
Number of vulnerabilities 41
Exploitation vector Remote access
Highest impact Code execution

Breakdown by Severity

High 22% Medium 51% Low 27%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 41 vulnerabilities.


1) Heap-based buffer overflow (CVE-ID: CVE-2026-34356)

CWE-ID: CWE-122 - Heap-based Buffer Overflow

CVSSv4: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to execute arbitrary code.

The vulnerability exists due to heap-based buffer overflow in ProxyPassReverseCookie* processing when interacting with malicious backend servers. A remote attacker can operate a malicious backend server to execute arbitrary code.


2) Allocation of Resources Without Limits or Throttling (CVE-ID: CVE-2026-29168)

CWE-ID: CWE-770 - Allocation of Resources Without Limits or Throttling

CVSSv4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to allocation of resources without limits or throttling in mod_md when processing OCSP response data. A remote attacker can provide crafted OCSP response data to cause a denial of service.


3) NULL pointer dereference (CVE-ID: CVE-2026-29169)

CWE-ID: CWE-476 - NULL Pointer Dereference

CVSSv4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to a NULL pointer dereference in mod_dav_lock when handling requests. A remote attacker can send a malicious request to cause a denial of service.

mod_dav_lock is not used internally by mod_dav or mod_dav_fs, and the only known use-case mentioned is mod_dav_svn earlier than version 1.2.0.


4) Cross-site scripting (CVE-ID: CVE-2026-29170)

CWE-ID: CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

CVSSv4: 5.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N]


The vulnerability allows a remote attacker to execute arbitrary script in a victim's browser.

The vulnerability exists due to cross-site scripting in mod_proxy_ftp HTML directory list generation when listing FTP directory contents via forward or reverse proxy configuration. A remote attacker can control FTP directory listing content to execute arbitrary script in a victim's browser.

The issue occurs during FTP directory listing generation.


5) Information Exposure Through Timing Discrepancy (CVE-ID: CVE-2026-33006)

CWE-ID: CWE-208 - Information Exposure Through Timing Discrepancy

CVSSv4: 7 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:H/SI:H/SA:N]


The vulnerability allows a remote attacker to bypass Digest authentication.

The vulnerability exists due to a timing side-channel in mod_auth_digest when processing Digest authentication. A remote attacker can perform a timing attack to bypass Digest authentication.


6) NULL pointer dereference (CVE-ID: CVE-2026-33007)

CWE-ID: CWE-476 - NULL Pointer Dereference

CVSSv4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to a NULL pointer dereference in mod_authn_socache when handling requests in a caching forward proxy configuration. A remote attacker can send a malicious request to cause a denial of service.

The issue crashes a child process only in a caching forward proxy configuration.


7) HTTP response splitting (CVE-ID: CVE-2026-33523)

CWE-ID: CWE-113 - Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Response Splitting')

CVSSv4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to manipulate HTTP responses.

The vulnerability exists due to improper neutralization of CRLF sequences in multiple Apache HTTP Server modules when forwarding a backend status line. A remote attacker can supply a malicious backend response to manipulate HTTP responses.

Exploitation requires an untrusted or compromised backend server.


8) Out-of-bounds read (CVE-ID: CVE-2026-33857)

CWE-ID: CWE-125 - Out-of-bounds read

CVSSv4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to disclose sensitive information.

The vulnerability exists due to an out-of-bounds read in mod_proxy_ajp AJP getter functions when parsing AJP data. A remote attacker can send a specially crafted AJP message to disclose sensitive information.

Exploitation requires Apache HTTP Server to connect to an untrusted or compromised AJP backend server.


9) Out-of-bounds read (CVE-ID: CVE-2026-34032)

CWE-ID: CWE-125 - Out-of-bounds read

CVSSv4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to disclose sensitive information.

The vulnerability exists due to improper null termination leading to an out-of-bounds read in mod_proxy_ajp ajp_msg_get_string when parsing AJP string data. A remote attacker can send a specially crafted AJP message to disclose sensitive information.

Exploitation requires Apache HTTP Server to connect to an untrusted or compromised AJP backend server.


10) Out-of-bounds read (CVE-ID: CVE-2026-34059)

CWE-ID: CWE-125 - Out-of-bounds read

CVSSv4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to disclose sensitive information.

The vulnerability exists due to a heap over-read in mod_proxy_ajp ajp_parse_data() when processing AJP messages from a backend server. A remote attacker can send a specially crafted AJP message to disclose sensitive information.

Exploitation requires Apache HTTP Server to connect to an untrusted or compromised AJP backend server.


11) Buffer overflow (CVE-ID: CVE-2026-34355)

CWE-ID: CWE-120 - Buffer overflow

CVSSv4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to buffer overflow in mod_proxy_html when processing content from an untrusted backend. A remote attacker can operate an untrusted backend to cause a denial of service.


12) Use-after-free (CVE-ID: CVE-2026-29167)

CWE-ID: CWE-416 - Use After Free

CVSSv4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to use-after-free in mod_ldap per-directory configuration when processing per-directory configuration. A local user can trigger processing of affected per-directory configuration to cause a denial of service.


13) Path traversal (CVE-ID: CVE-2026-42535)

CWE-ID: CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

CVSSv4: 7.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a remote user to cause a denial of service.

The vulnerability exists due to improper path handling in mod_dav_fs when a WebDAV content author directly manipulates trusted DAV property databases. A remote user can manipulate trusted DAV property databases to cause a denial of service.

The issue may cause child process crashes.


14) Heap-based buffer overflow (CVE-ID: CVE-2026-42536)

CWE-ID: CWE-122 - Heap-based Buffer Overflow

CVSSv4: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to execute arbitrary code.

The vulnerability exists due to heap-based buffer overflow in mod_xml2enc xml2StartParse when parsing untrusted content. A remote attacker can supply crafted content to execute arbitrary code.


15) Out-of-bounds read (CVE-ID: CVE-2026-43951)

CWE-ID: CWE-125 - Out-of-bounds read

CVSSv4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to out-of-bounds read in merge_response_headers when processing responses with mod_headers, mod_mime, and multiple response languages. A remote attacker can trigger processing of affected responses to cause a denial of service.

The issue occurs when mod_headers and mod_mime are used with multiple response languages.


16) Improper privilege management (CVE-ID: CVE-2026-44119)

CWE-ID: CWE-269 - Improper Privilege Management

CVSSv4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a local user to disclose sensitive information.

The vulnerability exists due to improper privilege management in expression handling in .htaccess across multiple modules when processing .htaccess expressions. A local user can author .htaccess expressions to disclose sensitive information.

The issue allows reading files with the privileges of the httpd user.


17) Out-of-bounds read (CVE-ID: CVE-2026-44185)

CWE-ID: CWE-125 - Out-of-bounds read

CVSSv4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to disclose sensitive information.

The vulnerability exists due to out-of-bounds read in mod_ssl OCSP send_request when sending outbound OCSP requests to an attacker-controlled OCSP server. A remote attacker can operate a malicious OCSP server to disclose sensitive information.


18) Infinite loop (CVE-ID: CVE-2026-44186)

CWE-ID: CWE-835 - Loop with Unreachable Exit Condition ('Infinite Loop')

CVSSv4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to an infinite loop in proxy_ftp_handler in mod_proxy_ftp when interacting with an attacker-controlled backend FTP server. A remote attacker can operate a malicious backend FTP server to cause a denial of service.


19) Out-of-bounds write (CVE-ID: CVE-2026-44631)

CWE-ID: CWE-787 - Out-of-bounds write

CVSSv4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to out-of-bounds write in ap_regname when processing crafted regular expressions in the configuration. A local user can place crafted regular expressions in the configuration to cause a denial of service.


20) Use-after-free (CVE-ID: CVE-2026-48913)

CWE-ID: CWE-416 - Use After Free

CVSSv4: 9.2 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to execute arbitrary code.

The vulnerability exists due to use-after-free in mod_http2 when file handles are already exhausted. A remote attacker can trigger request processing under file descriptor exhaustion conditions to execute arbitrary code.

Exploitation requires the server to have exhausted file handles.


21) Resource exhaustion (CVE-ID: CVE-2026-49975)

CWE-ID: CWE-400 - Resource exhaustion

CVSSv4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to uncontrolled resource consumption in the HTTP/2 request handling and HPACK header processing when handling crafted HTTP/2 requests that use repeated indexed header references and a stalled flow-control window. A remote attacker can send specially crafted HTTP/2 requests to cause a denial of service.

The issue is reachable in the default HTTP/2 configuration.


22) Cryptographic issues (CVE-ID: CVE-2025-49812)

CWE-ID: CWE-310 - Cryptographic Issues

CVSSv4: 6.3 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to perform MitM attack.

The vulnerability exists due to he way certain mod_ssl configurations handle TLS upgrades. A remote attacker can launch an HTTP desynchronisation attack, which allows a man-in-the-middle attacker to hijack an HTTP session via a TLS upgrade.

Note, only configurations using "SSLEngine optional" to enable TLS upgrades are affected.


23) Resource management error (CVE-ID: CVE-2023-43622)

CWE-ID: CWE-399 - Resource Management Errors

CVSSv4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to improper management of internal resources within the server when processing HTTP/2 connections with window size of 0. A remote attacker can exhaust available workers on the server and perform a denial of service (DoS) attack.


24) Resource exhaustion (CVE-ID: CVE-2023-44487) Exploited

CWE-ID: CWE-400 - Resource exhaustion

CVSSv4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to improperly control of consumption for internal resources when handling HTTP/2 requests with compressed HEADERS frames. A remote attacker can send a sequence of compressed HEADERS frames followed by RST_STREAM frames and perform a denial of service (DoS) attack, a.k.a. "Rapid Reset".

Note, the vulnerability is being actively exploited in the wild.


25) Resource management error (CVE-ID: CVE-2023-45802)

CWE-ID: CWE-399 - Resource Management Errors

CVSSv4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to improper management of internal resources within the server when handling HTTP/2 requests. A remote attacker can send multiple requests to the server and perform a denial of service (DoS) attack.


26) HTTP response splitting (CVE-ID: CVE-2024-42516)

CWE-ID: CWE-113 - Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Response Splitting')

CVSSv4: 6.3 [CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N]


The vulnerability allows a remote attacker to perform HTTP splitting attacks.

The vulnerability exists due to software does not correctly process CRLF character sequences. A remote attacker with ability to manipulate the Content-Type response headers of applications hosted or proxied by the server can send specially crafted request containing CRLF sequence and make the application to send a split HTTP response.

Successful exploitation of the vulnerability may allow an attacker perform cache poisoning attack.

Note, this vulnerability exists due a missing fix for #VU88151 (CVE-2023-38709).


27) Server-Side Request Forgery (SSRF) (CVE-ID: CVE-2024-43204)

CWE-ID: CWE-918 - Server-Side Request Forgery (SSRF)

CVSSv4: 6.3 [CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N]


The disclosed vulnerability allows a remote attacker to perform SSRF attacks.

The vulnerability exists due to insufficient validation of user-supplied input in mod_proxy . A remote attacker can send a specially crafted HTTP request and trick the application to initiate requests to arbitrary systems.

Note, the vulnerability exploitation requires an unlikely configuration where mod_headers is configured to modify the Content-Type request or response header with a value provided in the HTTP request.


28) Server-Side Request Forgery (SSRF) (CVE-ID: CVE-2024-43394)

CWE-ID: CWE-918 - Server-Side Request Forgery (SSRF)

CVSSv4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:L/SI:N/SA:N]


The disclosed vulnerability allows a remote attacker to perform SSRF attacks.

The vulnerability exists due to insufficient validation of user-supplied input when handling UNC paths on Windows. A remote attacker can trick the application into initiating requests to arbitrary systems and potentially leak NTLM hashes to a malicious server via mod_rewrite or apache expressions that pass unvalidated request input.

Note, the vulnerability affects Windows installations only. 



29) Improper Encoding or Escaping of Output (CVE-ID: CVE-2024-47252)

CWE-ID: CWE-116 - Improper Encoding or Escaping of Output

CVSSv4: 8.2 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to manipulate data in log files. 

The vulnerability exists due to improper input validation in mod_ssl. In a logging configuration where CustomLog is used with "%{varname}x" or "%{varname}c" to log variables provided by mod_ssl such as SSL_TLS_SNI, no escaping is performed by either mod_log_config or mod_ssl and unsanitized data provided by the client may appear in log files. A remote attacker can manipulate contents of log files. 


30) Security features bypass (CVE-ID: CVE-2025-23048)

CWE-ID: CWE-254 - Security Features

CVSSv4: 6.3 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to bypass implemented security restrictions.

The vulnerability exists due to access control bypass with session resumption in mod_ssl. A remote attacker can use the TLS 1.3 session resumption to bypass implemented access control.

Configurations are affected when mod_ssl is configured for multiple virtual hosts, with each restricted to a different set of trusted client certificates (for example with a different SSLCACertificateFile/Path setting). In such a case, a client trusted to access one virtual host may be able to access another virtual host, if SSLStrictSNIVHostCheck is not enabled in either virtual host.


31) Resource management error (CVE-ID: CVE-2025-49630)

CWE-ID: CWE-399 - Resource Management Errors

CVSSv4: 8.2 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to improper management of internal resources in mod_proxy_http2. A remote attacker can send specially crafted requests to the server and perform a denial of service (DoS) attack.

Successful exploitation of the vulnerability requires that the reverse proxy is configured for an HTTP/2 backend, with ProxyPreserveHost set to "on".


32) Out-of-bounds read (CVE-ID: CVE-2023-31122)

CWE-ID: CWE-125 - Out-of-bounds read

CVSSv4: 8.2 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to a boundary condition within mod_macro module. A remote attacker can send specially crafted requests to the server, trigger an out-of-bounds read error and perform a denial of service (DoS) attack.


33) Resource management error (CVE-ID: CVE-2025-53020)

CWE-ID: CWE-399 - Resource Management Errors

CVSSv4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to improper management of internal resources within the server when handling HTTP/2 requests. A remote attacker can send multiple requests to the server and perform a denial of service (DoS) attack.


34) Integer overflow (CVE-ID: CVE-2025-55753)

CWE-ID: CWE-190 - Integer overflow

CVSSv4: 6.3 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to perform a denial of service attack.

The vulnerability exists due to an integer overflow in mod_md (ACME) in the case of failed ACME certificate renewal. The web server will set the backoff timer becoming 0 after a number of failures (~30 days in default configurations), leading to a denial of service condition.


35) Improper Neutralization of Server-Side Includes (SSI) Within a Web Page (CVE-ID: CVE-2025-58098)

CWE-ID: CWE-97 - Improper Neutralization of Server-Side Includes (SSI) Within a Web Page

CVSSv4: 6.3 [CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to execute arbitrary commands.

The vulnerability exists due to insufficient input validation with Server Side Includes (SSI) enabled and mod_cgid (but not mod_cgi). The web server passes the shell-escaped query string to #exec cmd="..." directives. A remote attacker can send a specially crafted HTTP request to the server and potentially execute arbitrary code.


36) Server-Side Request Forgery (SSRF) (CVE-ID: CVE-2025-59775)

CWE-ID: CWE-918 - Server-Side Request Forgery (SSRF)

CVSSv4: 6.3 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]


The disclosed vulnerability allows a remote attacker to perform SSRF attacks.

The vulnerability exists due to insufficient validation of user-supplied input when AllowEncodedSlashes is "On" and MergeSlashes is "Off". A remote attacker can send a specially crafted HTTP request and force the web server into leaking NTLM hashes. 

Note, the vulnerability affects Windows installations only. 


37) Code injection (CVE-ID: CVE-2025-65082)

CWE-ID: CWE-74 - Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')

CVSSv4: 2 [CVSS:4.0/AV:L/AC:H/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a local user to affect web server behavior. 

The vulnerability exists due to improper input validation when handling environment variables set via the Apache configuration. A local user can set specially crafted values that supersede variables calculated by the server for CGI programs.


38) Input validation error (CVE-ID: CVE-2025-66200)

CWE-ID: CWE-20 - Improper input validation

CVSSv4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a local user to bypass implemented security restrictions.

The vulnerability exists due to insufficient validation of user-supplied input when parsing the RequestHeader directive in .htaccess files. A local user can bypass mod_userdir+suexec security measures via AllowOverride FileInfo and run certain CGI scripts under an unexpected userid.


39) Double free (CVE-ID: CVE-2026-23918)

CWE-ID: CWE-415 - Double Free

CVSSv4: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to cause a denial of service and possibly execute arbitrary code.

The vulnerability exists due to a double free in Apache HTTP Server HTTP/2 handling when processing an early reset. A remote attacker can trigger an early reset condition to cause a denial of service and possibly execute arbitrary code.

The issue is specific to the HTTP/2 protocol.


40) Improper access control (CVE-ID: CVE-2026-24072)

CWE-ID: CWE-284 - Improper Access Control

CVSSv4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a local user to disclose sensitive information.

The vulnerability exists due to improper access control in various Apache HTTP Server modules when evaluating ap_expr from .htaccess files. A local user can create a crafted .htaccess expression to disclose sensitive information.

The issue affects local .htaccess authors and allows reading files with the privileges of the httpd user.


41) Heap-based buffer overflow (CVE-ID: CVE-2026-28780)

CWE-ID: CWE-122 - Heap-based Buffer Overflow

CVSSv4: 9.2 [CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to cause a denial of service or potentially execute arbitrary code.

The vulnerability exists due to a heap-based buffer overflow in mod_proxy_ajp ajp_msg_check_header() when processing AJP messages from a backend server. A remote attacker can send a specially crafted AJP message to cause a denial of service or potentially execute arbitrary code.

The malicious AJP server can cause 4 attacker-controlled bytes to be written past the end of a heap-based buffer.


Remediation

Install update from vendor's website.