SB2021092301 - Multiple vulnerabilities in cPanel EasyApache
Published: September 23, 2021 Updated: December 18, 2023
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 8 secuirty vulnerabilities.
1) Double Free (CVE-ID: CVE-2021-22945)
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to a boundary error when sending data to an MQTT server. A remote attacker with ability to control libcurl input can trigger a double free error and perform a denial of service (DoS) attack.
2) Cleartext transmission of sensitive information (CVE-ID: CVE-2021-22946)
The vulnerability allows a remote attacker to gain access to sensitive information.
The vulnerability exists due to an error, related to incorrect enforcement of the --ssl-reqd option on the command line or CURLOPT_USE_SSL setting set to CURLUSESSL_CONTROL or CURLUSESSL_ALL with libcurl. A remote attacker with control over the IMAP, POP3 or FTP server can send a specially crafted but perfectly legitimate response to the libcurl client and force it silently to continue its operations without TLS encryption and transmit data in clear text over the network.
3) Insufficient verification of data authenticity (CVE-ID: CVE-2021-22947)
The vulnerability allows a remote attacker to perform MitM attack.
The vulnerability exists in the way libcurl handles the STARTTLS negotiation process. When curl connects to an IMAP, POP3, SMTP or FTP server to exchange data securely using STARTTLS to upgrade the connection to TLS level, the server can still respond and send back multiple responses before the TLS upgrade. Such multiple "pipelined" responses are cached by curl. curl would then upgrade to TLS but not flush the in-queue of cached responses and instead use and trust the responses it got before the TLS handshake as if they were authenticated.
Using this flaw, it allows a Man-In-The-Middle attacker to first inject the fake responses, then pass-through the TLS traffic from the legitimate server and trick curl into sending data back to the user thinking the attacker's injected data comes from the TLS-protected server.
Over POP3 and IMAP an attacker can inject fake response data.
4) Server-Side Request Forgery (SSRF) (CVE-ID: CVE-2021-40438)
The disclosed vulnerability allows a remote attacker to perform SSRF attacks.
The vulnerability exists due to insufficient validation of user-supplied input within the mod_proxy module in Apache HTTP Server. A remote attacker can send a specially crafted HTTP request with a chosen uri-path and trick the web server to initiate requests to arbitrary systems.
Successful exploitation of this vulnerability may allow a remote attacker gain access to sensitive data, located in the local network or send malicious requests to other servers from the vulnerable system.
5) Buffer overflow (CVE-ID: CVE-2021-39275)
The vulnerability allows a remote attacker to execute arbitrary code on the target system or perform a denial of service attack.
The vulnerability exists due to a boundary error within the ap_escape_quotes() function. A remote attacker can send a specially crafted request to the web server, trigger memory corruption and execute arbitrary code on the target system.
Successful exploitation of this vulnerability may result in complete compromise of vulnerable system but requires that the Apache module passes untrusted data to the affected function.
According to vendor, No included modules pass untrusted data to these functions
6) Out-of-bounds read (CVE-ID: CVE-2021-36160)
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to a boundary condition in the mod_proxy_uwsgi module in Apache HTTP Server. A remote attacker can send an HTTP request with specially crafted uri-path, trigger an out-of-bounds read and perform a denial of service (DoS) attack.
7) NULL pointer dereference (CVE-ID: CVE-2021-34798)
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to a NULL pointer dereference error. A remote attacker can send a specially crafted HTTP request to the affected web server and perform a denial of service (DoS) attack.
8) Inconsistent interpretation of HTTP requests (CVE-ID: CVE-2021-33193)
The vulnerability allows a remote attacker to preform HTTP/2 request smuggling attacks.
The vulnerability exists due to improper validation of HTTP/2 requests in mod_proxy in Apache HTTP Server. A remote attacker can send a specially crafted HTTP/2 request to the server and smuggle arbitrary HTTP headers.
Successful exploitation of vulnerability may allow an attacker to poison web server cache and perform phishing attacks.
Remediation
Install update from vendor's website.