NULL pointer dereference in Apache HTTP Server
CVE-2021-26690
Apache HTTP Server versions 2.4.0 to 2.4.46 A specially crafted Cookie header handled by mod_session can cause a NULL pointer dereference and crash, leading to a possible Denial Of Service
Published · last modified .
CVSS v3 metric
CVSS v3 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.
EPSS exploit prediction
EPSS: 0.653 (99.3th percentile), scored .
High probability of exploitation in the next 30 days — patch promptly. 99th percentile — 99.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.653 · newest: 0.653 · change: 0.000
Affected products
- Apache HTTP Server
- Apache Software Foundation HTTP Server — versions 2.4.46, 2.4.43, 2.4.41
- Oracle Enterprise Manager Ops Center — versions 12.4.0.0
- Oracle Instantis Enterprisetrack — versions 17.1, 17.2, 17.3
- Oracle Zfs Storage Appliance Kit — versions 8.8
- Debian Linux — versions 9.0, 10.0
- Fedoraproject Fedora — versions 34, 35
Weakness classification (CWE)
Public proof-of-concept exploits
References
- httpd.apache.org/security/vulnerabilities_24.html (Release Notes, Vendor Advisory)
- lists.apache.org/thread.html/re026d3da9d7824bd93b9f871c0fdda978d960c7e62d8c43cb… (Mailing List, Vendor Advisory)
- lists.apache.org/thread.html/rae406c1d19c0dfd3103c96923dadac2af1cd0bad6905ab1ed… (mailing-list)
- lists.apache.org/thread.html/r7f2b70b621651548f4b6f027552f1dd91705d7111bb5d15cd… (mailing-list)
- www.openwall.com/lists/oss-security/2021/06/10/6 (mailing-list, Mailing List, Third Party Advisory)
- lists.debian.org/debian-lts-announce/2021/07/msg00006.html (mailing-list, Mailing List, Third Party Advisory)
- www.debian.org/security/2021/dsa-4937 (vendor-advisory, Mailing List, Third Party Advisory)
- security.gentoo.org/glsa/202107-38 (vendor-advisory, Third Party Advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
Frequently asked questions
- What is CVE-2021-26690?
- CVE-2021-26690 is a high-severity vulnerability in Apache HTTP Server, classified under NULL Pointer Dereference. CVSS score: 7.5/10. Published 2021-06-10.
- How severe is CVE-2021-26690?
- High severity. CVSS v3 base score is 7.5 out of 10.
- Is CVE-2021-26690 known to be exploited?
- 22 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.