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
Does this matter?
EPSS puts the probability of exploitation in the next 30 days at 65.3%, higher than 99% of all known CVEs. Patch or mitigate before the next change window.
Description
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
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 65.31% probability · 99th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-476
- Affected
- apache/http server · debian/debian linux · fedoraproject/fedora · oracle/enterprise manager ops center · oracle/instantis enterprisetrack · oracle/zfs storage appliance kit
- Source
- security@apache.org
EPSS 65.3% since 26 October 2026; no change recorded yet. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- http://httpd.apache.org/security/vulnerabilities_24.htmlRelease Notes, Vendor Advisory
- http://www.openwall.com/lists/oss-security/2021/06/10/6Mailing List, Third Party Advisory
- https://lists.apache.org/thread.html/r7f2b70b621651548f4b6f027552f1dd91705d7111bb5d15cda0a68dd%40%3Cdev.httpd.apache.org%3E
- https://lists.apache.org/thread.html/rae406c1d19c0dfd3103c96923dadac2af1cd0bad6905ab1ede153865%40%3Cannounce.httpd.apache.org%3E
- https://lists.apache.org/thread.html/re026d3da9d7824bd93b9f871c0fdda978d960c7e62d8c43cba8d0bf3%40%3Ccvs.httpd.apache.org%3EMailing List, Vendor Advisory
- https://lists.debian.org/debian-lts-announce/2021/07/msg00006.htmlMailing List, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SPBR6WUYBJNACHKE65SPL7TJOHX7RHWD/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZNCYSR3BXT36FFF4XTCPL3HDQK4VP45R/
- https://security.gentoo.org/glsa/202107-38Third Party Advisory
- https://security.netapp.com/advisory/ntap-20210702-0001/Third Party Advisory
- https://www.debian.org/security/2021/dsa-4937Mailing List, Third Party Advisory
- https://www.oracle.com/security-alerts/cpuoct2021.htmlThird Party Advisory
- http://httpd.apache.org/security/vulnerabilities_24.htmlRelease Notes, Vendor Advisory
- http://www.openwall.com/lists/oss-security/2021/06/10/6Mailing List, Third Party Advisory
- https://lists.apache.org/thread.html/r7f2b70b621651548f4b6f027552f1dd91705d7111bb5d15cda0a68dd%40%3Cdev.httpd.apache.org%3E
- https://lists.apache.org/thread.html/rae406c1d19c0dfd3103c96923dadac2af1cd0bad6905ab1ede153865%40%3Cannounce.httpd.apache.org%3E
- https://lists.apache.org/thread.html/re026d3da9d7824bd93b9f871c0fdda978d960c7e62d8c43cba8d0bf3%40%3Ccvs.httpd.apache.org%3EMailing List, Vendor Advisory
- https://lists.debian.org/debian-lts-announce/2021/07/msg00006.htmlMailing List, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SPBR6WUYBJNACHKE65SPL7TJOHX7RHWD/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZNCYSR3BXT36FFF4XTCPL3HDQK4VP45R/
- https://security.gentoo.org/glsa/202107-38Third Party Advisory
- https://security.netapp.com/advisory/ntap-20210702-0001/Third Party Advisory
- https://www.debian.org/security/2021/dsa-4937Mailing List, Third Party Advisory
- https://www.oracle.com/security-alerts/cpuoct2021.htmlThird Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.