Multiple vulnerabilities in Apache HTTP Server



Published: 2021-09-17 | Updated: 2022-08-07
Risk High
Patch available YES
Number of vulnerabilities 4
CVE-ID CVE-2021-34798
CVE-2021-36160
CVE-2021-39275
CVE-2021-40438
CWE-ID CWE-476
CWE-125
CWE-119
CWE-918
Exploitation vector Network
Public exploit Vulnerability #4 is being exploited in the wild.
Vulnerable software
Subscribe
Apache HTTP Server
Server applications / Web servers

Vendor Apache Foundation

Security Bulletin

This security bulletin contains information about 4 vulnerabilities.

1) NULL pointer dereference

EUVDB-ID: #VU56681

Risk: Medium

CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-34798

CWE-ID: CWE-476 - NULL Pointer Dereference

Exploit availability: No

Description

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.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Apache HTTP Server: 2.4.0 - 2.4.48


CPE2.3 External links

http://httpd.apache.org/security/vulnerabilities_24.html

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected application in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

2) Out-of-bounds read

EUVDB-ID: #VU56680

Risk: Medium

CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-36160

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

Exploit availability: No

Description

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.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Apache HTTP Server: 2.4.32 - 2.4.48


CPE2.3 External links

http://httpd.apache.org/security/vulnerabilities_24.html
http://lists.apache.org/thread.html/ree7519d71415ecdd170ff1889cab552d71758d2ba2904a17ded21a70@%3Ccvs.httpd.apache.org%3E
http://lists.apache.org/thread.html/re4162adc051c1a0a79e7a24093f3776373e8733abaff57253fef341d@%3Ccvs.httpd.apache.org%3E

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected application in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

3) Buffer overflow

EUVDB-ID: #VU56679

Risk: Medium

CVSSv3.1: 4.9 [CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-39275

CWE-ID: CWE-119 - Improper Restriction of Operations within the Bounds of a Memory Buffer

Exploit availability: No

Description

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

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Apache HTTP Server: 2.4.0 - 2.4.48


CPE2.3 External links

http://httpd.apache.org/security/vulnerabilities_24.html

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected application in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

4) Server-Side Request Forgery (SSRF)

EUVDB-ID: #VU56678

Risk: High

CVSSv3.1: 8.1 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-40438

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

Exploit availability: Yes

Description

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.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Apache HTTP Server: 2.4.0 - 2.4.48


CPE2.3 External links

http://httpd.apache.org/security/vulnerabilities_24.html

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected application in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.



###SIDEBAR###