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CVE-2021-26690

mod_session NULL pointer dereference

HIGH
7.5
CVSS Score
Published: June 10, 2021 at 07:10 AM UTC
Updated: June 17, 2026 at 03:43 AM UTC
6 products affected across 4 vendorsDebian LinuxFedoraHTTP Server

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Severity
HIGH7.5
Exploit prediction
EPSS 65%

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

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

References (12)

x_refsource_MISCRelease NotesVendor Advisory
Source: [email protected]
http://httpd.apache.org/security/vulnerabilities_24.html
Mailing Listx_refsource_MLISTThird Party Advisory
Source: [email protected]
http://www.openwall.com/lists/oss-security/2021/06/10/6
Mailing Listx_refsource_MLIST
Source: [email protected]
https://lists.apache.org/thread.html/r7f2b70b621651548f4b6f027552f1dd91705d7111bb5d15cda0a68dd%40%3Cdev.httpd.apache.org%3E
Mailing Listx_refsource_MLIST
Source: [email protected]
https://lists.apache.org/thread.html/rae406c1d19c0dfd3103c96923dadac2af1cd0bad6905ab1ede153865%40%3Cannounce.httpd.apache.org%3E
x_refsource_MISCMailing ListVendor Advisory
Source: [email protected]
https://lists.apache.org/thread.html/re026d3da9d7824bd93b9f871c0fdda978d960c7e62d8c43cba8d0bf3%40%3Ccvs.httpd.apache.org%3E
Mailing Listx_refsource_MLISTThird Party Advisory
Source: [email protected]
https://lists.debian.org/debian-lts-announce/2021/07/msg00006.html
Vendor Advisoryx_refsource_FEDORA
Source: [email protected]
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SPBR6WUYBJNACHKE65SPL7TJOHX7RHWD/
Vendor Advisoryx_refsource_FEDORA
Source: [email protected]
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZNCYSR3BXT36FFF4XTCPL3HDQK4VP45R/

CVSS

7.5HIGH[email protected]
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-476

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