CVE-2021-26690

mod_session NULL pointer dereference

Severity Score

7.5

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

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

Apache HTTP Server versiones 2.4.0 a 2.4.46, un encabezado de Cookie especialmente diseñado y gestionado por la función mod_session puede causar una desviación del puntero NULL y un fallo, lo que puede causar una denegación de servicio

A NULL pointer dereference was found in Apache httpd mod_session. The highest threat from this vulnerability is to system availability.

Red Hat JBoss Core Services is a set of supplementary software for Red Hat JBoss middleware products. This software, such as Apache HTTP Server, is common to multiple JBoss middleware products, and is packaged under Red Hat JBoss Core Services to allow for faster distribution of updates, and for a more consistent update experience. This release adds the new Apache HTTP Server 2.4.37 Service Pack 10 packages that are part of the JBoss Core Services offering. This release serves as a replacement for Red Hat JBoss Core Services Apache HTTP Server 2.4.37 Service Pack 9 and includes bug fixes and enhancements. Issues addressed include buffer over-read, heap overflow, integer overflow, and null pointer vulnerabilities.

*Credits: This issue was discovered and reported by GHSL team member @antonio-morales (Antonio Morales)

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Attack Vector

Network

Attack Complexity

Low

Authentication

None

Confidentiality

None

Integrity

None

Availability

Partial

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2021-02-04 CVE Reserved
2021-06-10 CVE Published
2024-08-03 CVE Updated
2024-11-01 First Exploit
2025-04-01 EPSS Updated
---------- Exploited in Wild
---------- KEV Due Date

CWE

CWE-476: NULL Pointer Dereference

CAPEC

References (17)

URL	Tag	Source
http://www.openwall.com/lists/oss-security/2021/06/10/6	Mailing List
https://lists.apache.org/thread.html/r7f2b70b621651548f4b6f027552f1dd91705d7111bb5d15cda0a68dd%40%3Cdev.httpd.apache.org%3E	Mailing List
https://lists.apache.org/thread.html/rae406c1d19c0dfd3103c96923dadac2af1cd0bad6905ab1ede153865%40%3Cannounce.httpd.apache.org%3E	Mailing List
https://lists.debian.org/debian-lts-announce/2021/07/msg00006.html	Mailing List
https://security.netapp.com/advisory/ntap-20210702-0001	Third Party Advisory
https://www.oracle.com/security-alerts/cpuoct2021.html	Third Party Advisory

URL	Date	SRC
https://github.com/7own/CVE-2021-26690---Apache-mod_session	2024-11-01
https://github.com/0xdeviner/CVE-2021-26690	2024-11-29
https://github.com/danielduan2002/CVE-2021-26690	2024-12-27

URL	Date	SRC

URL	Date	SRC
http://httpd.apache.org/security/vulnerabilities_24.html	2023-11-07
https://lists.apache.org/thread.html/re026d3da9d7824bd93b9f871c0fdda978d960c7e62d8c43cba8d0bf3%40%3Ccvs.httpd.apache.org%3E	2023-11-07
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SPBR6WUYBJNACHKE65SPL7TJOHX7RHWD	2023-11-07
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZNCYSR3BXT36FFF4XTCPL3HDQK4VP45R	2023-11-07
https://security.gentoo.org/glsa/202107-38	2023-11-07
https://www.debian.org/security/2021/dsa-4937	2023-11-07
https://access.redhat.com/security/cve/CVE-2021-26690	2021-11-10
https://bugzilla.redhat.com/show_bug.cgi?id=1966729	2021-11-10

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Apache Search vendor "Apache"		Http Server Search vendor "Apache" for product "Http Server"				>= 2.4.0 <= 2.4.46 Search vendor "Apache" for product "Http Server" and version " >= 2.4.0 <= 2.4.46"		-		Affected
Debian Search vendor "Debian"		Debian Linux Search vendor "Debian" for product "Debian Linux"				9.0 Search vendor "Debian" for product "Debian Linux" and version "9.0"		-		Affected
Debian Search vendor "Debian"		Debian Linux Search vendor "Debian" for product "Debian Linux"				10.0 Search vendor "Debian" for product "Debian Linux" and version "10.0"		-		Affected
Fedoraproject Search vendor "Fedoraproject"		Fedora Search vendor "Fedoraproject" for product "Fedora"				34 Search vendor "Fedoraproject" for product "Fedora" and version "34"		-		Affected
Fedoraproject Search vendor "Fedoraproject"		Fedora Search vendor "Fedoraproject" for product "Fedora"				35 Search vendor "Fedoraproject" for product "Fedora" and version "35"		-		Affected
Oracle Search vendor "Oracle"		Enterprise Manager Ops Center Search vendor "Oracle" for product "Enterprise Manager Ops Center"				12.4.0.0 Search vendor "Oracle" for product "Enterprise Manager Ops Center" and version "12.4.0.0"		-		Affected
Oracle Search vendor "Oracle"		Instantis Enterprisetrack Search vendor "Oracle" for product "Instantis Enterprisetrack"				17.1 Search vendor "Oracle" for product "Instantis Enterprisetrack" and version "17.1"		-		Affected
Oracle Search vendor "Oracle"		Instantis Enterprisetrack Search vendor "Oracle" for product "Instantis Enterprisetrack"				17.2 Search vendor "Oracle" for product "Instantis Enterprisetrack" and version "17.2"		-		Affected
Oracle Search vendor "Oracle"		Instantis Enterprisetrack Search vendor "Oracle" for product "Instantis Enterprisetrack"				17.3 Search vendor "Oracle" for product "Instantis Enterprisetrack" and version "17.3"		-		Affected
Oracle Search vendor "Oracle"		Zfs Storage Appliance Kit Search vendor "Oracle" for product "Zfs Storage Appliance Kit"				8.8 Search vendor "Oracle" for product "Zfs Storage Appliance Kit" and version "8.8"		-		Affected