CVE-2021-31618 Detail

Current Description

Apache HTTP Server protocol handler for the HTTP/2 protocol checks received request headers against the size limitations as configured for the server and used for the HTTP/1 protocol as well. On violation of these restrictions and HTTP response is sent to the client with a status code indicating why the request was rejected. This rejection response was not fully initialised in the HTTP/2 protocol handler if the offending header was the very first one received or appeared in a a footer. This led to a NULL pointer dereference on initialised memory, crashing reliably the child process. Since such a triggering HTTP/2 request is easy to craft and submit, this can be exploited to DoS the server. This issue affected mod_http2 1.15.17 and Apache HTTP Server version 2.4.47 only. Apache HTTP Server 2.4.47 was never released.


View Analysis Description

Severity



CVSS 3.x Severity and Metrics:

NIST CVSS score
NIST: NVD
Base Score:  7.5 HIGH
Vector:  CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H


NVD Analysts use publicly available information to associate vector strings and CVSS scores. We also display any CVSS information provided within the CVE List from the CNA.

Note: NVD Analysts have published a CVSS score for this CVE based on publicly available information at the time of analysis. The CNA has not provided a score within the CVE List.

References to Advisories, Solutions, and Tools

By selecting these links, you will be leaving NIST webspace. We have provided these links to other web sites because they may have information that would be of interest to you. No inferences should be drawn on account of other sites being referenced, or not, from this page. There may be other web sites that are more appropriate for your purpose. NIST does not necessarily endorse the views expressed, or concur with the facts presented on these sites. Further, NIST does not endorse any commercial products that may be mentioned on these sites. Please address comments about this page to nvd@nist.gov.

Hyperlink Resource
http://httpd.apache.org/security/vulnerabilities_24.html Release Notes  Vendor Advisory 
http://www.openwall.com/lists/oss-security/2021/06/10/9 Mailing List  Third Party Advisory 
https://lists.apache.org/thread.html/r14b66ef0f4f569fd515a3f96cd4eb58bd9a8ff525cc326bb0359664f@%3Ccvs.httpd.apache.org%3E Mailing List  Vendor Advisory 
https://lists.apache.org/thread.html/r783b6558abf3305b17ea462bed4bd66d82866438999bf38cef6d11d1@%3Ccvs.httpd.apache.org%3E Mailing List  Vendor Advisory 
https://lists.debian.org/debian-lts-announce/2021/07/msg00006.html
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/2NKJ3ZA3FTSZ2QBBPKS6BYGAWYRABNQQ/ Mailing List  Third Party Advisory 
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/A73QJ4HPUMU26I6EULG6SCK67TUEXZYR/ Mailing List  Third Party Advisory 
https://seclists.org/oss-sec/2021/q2/206 Mailing List  Third Party Advisory 
https://security.gentoo.org/glsa/202107-38
https://www.debian.org/security/2021/dsa-4937

Weakness Enumeration

CWE-ID CWE Name Source
CWE-476 NULL Pointer Dereference cwe source acceptance level NIST   Contributor acceptance level Apache Software Foundation  

Known Affected Software Configurations Switch to CPE 2.2

CPEs loading, please wait.

Denotes Vulnerable Software
Are we missing a CPE here? Please let us know.

Change History

7 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2021-31618
NVD Published Date:
06/15/2021
NVD Last Modified:
07/17/2021
Source:
Apache Software Foundation