CVE-2021-41524

null pointer dereference in h2 fuzzing

Description

While fuzzing the 2.4.49 httpd, a new null pointer dereference was detected during HTTP/2 request processing, allowing an external source to DoS the server. This requires a specially crafted request. The vulnerability was recently introduced in version 2.4.49. No exploit is known to the project.

Remediation

Workaround:

  • Disable the HTTP/2 protocol.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 6.59% Top 10%
Vendor Advisory fedoraproject.org Vendor Advisory cisco.com Vendor Advisory fedoraproject.org Vendor Advisory gentoo.org Vendor Advisory apache.org
Affected: Apache Software Foundation Apache HTTP Server
Published at:
Updated at:

References

Link Tags
https://httpd.apache.org/security/vulnerabilities_24.html vendor advisory
http://www.openwall.com/lists/oss-security/2021/10/05/1 third party advisory mailing list
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/DSM6UWQICBJ2TU727RENU3HBKEAFLT6T/ vendor advisory
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-apache-httpd-pathtrv-LAzg68cZ third party advisory vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/EUVJVRJRBW5QVX4OY3NOHZDQ3B3YOTSG/ vendor advisory
https://www.oracle.com/security-alerts/cpujan2022.html third party advisory patch
https://security.netapp.com/advisory/ntap-20211029-0009/ third party advisory
https://security.gentoo.org/glsa/202208-20 third party advisory vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-41524?
CVE-2021-41524 has been scored as a high severity vulnerability.
How to fix CVE-2021-41524?
As a workaround for remediating CVE-2021-41524: Disable the HTTP/2 protocol.
Is CVE-2021-41524 being actively exploited in the wild?
It is possible that CVE-2021-41524 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~7% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-41524?
CVE-2021-41524 affects Apache Software Foundation Apache HTTP Server.
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