CVE-2021-31618

Summary

CVECVE-2021-31618
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2021-06-15 09:15:00 UTC
Updated2023-11-07 03:34:00 UTC
DescriptionApache 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.

Risk And Classification

Problem Types: CWE-476

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Application Apache Http Server 1.15.17 All All All
Application Apache Http Server 2.4.47 All All All
Operating System Debian Debian Linux 10.0 All All All
Operating System Debian Debian Linux 9.0 All All All
Operating System Fedoraproject Fedora 33 All All All
Operating System Fedoraproject Fedora 34 All All All
Application Oracle Enterprise Manager Ops Center 12.4.0.0 All All All
Application Oracle Instantis Enterprisetrack 17.1 All All All
Application Oracle Instantis Enterprisetrack 17.2 All All All
Application Oracle Instantis Enterprisetrack 17.3 All All All
Application Oracle Zfs Storage Appliance Kit 8.8 All All All

References

ReferenceSourceLinkTags
Apache HTTP Server 2.4 vulnerabilities - The Apache HTTP Server Project MISC httpd.apache.org
[SECURITY] Fedora 34 Update: mod_http2-1.15.19-1.fc34 - package-announce - Fedora Mailing-Lists FEDORA lists.fedoraproject.org
[SECURITY] Fedora 34 Update: mod_http2-1.15.19-1.fc34 - package-announce - Fedora Mailing-Lists lists.fedoraproject.org
[httpd-cvs] 20210615 svn commit: r1890801 - /httpd/site/trunk/content/security/json/CVE-2021-31618.json lists.apache.org
Oracle Critical Patch Update Advisory - October 2021 MISC www.oracle.com
Debian -- Security Information -- DSA-4937-1 apache2 DEBIAN www.debian.org
[SECURITY] Fedora 33 Update: mod_http2-1.15.19-1.fc33 - package-announce - Fedora Mailing-Lists FEDORA lists.fedoraproject.org
[SECURITY] [DLA 2706-1] apache2 security update MLIST lists.debian.org
Pony Mail! MLIST lists.apache.org
Apache: Multiple vulnerabilities (GLSA 202107-38) — Gentoo security GENTOO security.gentoo.org
Pony Mail! MLIST lists.apache.org
CVE-2021-31618 Apache HTTP Server Vulnerability in NetApp Products | NetApp Product Security CONFIRM security.netapp.com
oss-security - CVE-2021-31618: Apache httpd: NULL pointer dereference on specially crafted HTTP/2 request MLIST www.openwall.com
[httpd-cvs] 20210615 svn commit: r1075782 - in /websites/staging/httpd/trunk/content: ./ security/json/CVE-2021-31618.json security/vulnerabilities_24.html lists.apache.org
oss-sec: CVE-2021-31618: Apache httpd: NULL pointer dereference on specially crafted HTTP/2 request MISC seclists.org
[SECURITY] Fedora 33 Update: mod_http2-1.15.19-1.fc33 - package-announce - Fedora Mailing-Lists lists.fedoraproject.org
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Vendor Comments And Credit

Discovery Credit

LEGACY: Apache HTTP server would like to thank LI ZHI XIN from NSFocus for reporting this.

Legacy QID Mappings

  • 150403 Apache HTTP Server NULL pointer dereference (CVE-2021-31618)
  • 178699 Debian Security Update for apache2 (DSA 4937-1)
  • 178701 Debian Security Update for apache2 (DLA 2706-1)
  • 180247 Debian Security Update for apache2 (CVE-2021-31618)
  • 239451 Red Hat Update for Red Hat JBoss Core Services Apache HTTP Server 2.4.37 SP8 (RHSA-2021:2472)
  • 281653 Fedora Security Update for mod_http2 (FEDORA-2021-181f29c392)
  • 281654 Fedora Security Update for mod_http2 (FEDORA-2021-051639aad4)
  • 296053 Oracle Solaris 11.4 Support Repository Update (SRU) 35.94.4 Missing (CPUJUL2021)
  • 352395 Amazon Linux Security Advisory for httpd: ALAS2-2021-1659
  • 352406 Amazon Linux Security Advisory for httpd: ALAS2-2021-1672
  • 352458 Amazon Linux Security Advisory for mod_http2: ALAS2-2021-1678
  • 500021 Alpine Linux Security Update for apache2
  • 503712 Alpine Linux Security Update for apache2
  • 690107 Free Berkeley Software Distribution (FreeBSD) Security Update for apache httpd (cce76eca-ca16-11eb-9b84-d4c9ef517024)
  • 710030 Gentoo Linux Apache Multiple vulnerabilities (GLSA 202107-38)
  • 730108 Apache HTTP Server Denial of Service Vulnerability
  • 730109 Apache HTTP Server Multiple Vulnerabilities
  • 750660 SUSE Enterprise Linux Security Update for apache2 (SUSE-SU-2021:2004-1)
  • 750662 SUSE Enterprise Linux Security Update for apache2 (SUSE-SU-2021:2006-1)
  • 750719 OpenSUSE Security Update for apache2 (openSUSE-SU-2021:0908-1)
  • 750813 OpenSUSE Security Update for apache2 (openSUSE-SU-2021:2127-1)
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