CVE-2021-27645

glibc: Use-after-free in addgetnetgrentX function in netgroupcache.c

Severity Score

2.5

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

The nameserver caching daemon (nscd) in the GNU C Library (aka glibc or libc6) 2.29 through 2.33, when processing a request for netgroup lookup, may crash due to a double-free, potentially resulting in degraded service or Denial of Service on the local system. This is related to netgroupcache.c.

El demonio de almacenamiento en caché nameserver (nscd) en el GNU C Library (también se conoce como glibc o libc6) versiones 2.29 hasta 2.33, cuando se procesa una petición de búsqueda de netgroup, puede cometer un fallo debido a una doble liberación, potencialmente resultando en un servicio degradado o denegación de servicio en el sistema local. Esto está relacionado con el archivo netgroupcache.c

The nameserver caching daemon (nscd) in the GNU C Library (aka glibc or libc6), when processing a request for netgroup lookup, may crash due to a double-free, potentially resulting in degraded service or Denial of Service on the local system.

*Credits: N/A

Attack Vector

Local

Attack Complexity

High

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

Low

Attack Vector

Local

Attack Complexity

Medium

Authentication

None

Confidentiality

None

Integrity

None

Availability

Partial

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2021-02-24 CVE Reserved
2021-02-24 CVE Published
2023-03-08 EPSS Updated
2024-08-03 CVE Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CWE-415: Double Free
CWE-416: Use After Free

CAPEC

References (7)

URL	Tag	Source
https://lists.debian.org/debian-lts-announce/2022/10/msg00021.html	Mailing List

URL	Date	SRC

URL	Date	SRC
https://sourceware.org/bugzilla/show_bug.cgi?id=27462	2023-11-07

URL	Date	SRC
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7LZNT6KTMCCWPWXEOGSHD3YLYZKUGMH5	2023-11-07
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/I7TS26LIZSOBLGJEZMJX4PXT5BQDE2WS	2023-11-07
https://security.gentoo.org/glsa/202107-07	2023-11-07
https://access.redhat.com/security/cve/CVE-2021-27645	2021-11-09
https://bugzilla.redhat.com/show_bug.cgi?id=1932589	2021-11-09

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Gnu Search vendor "Gnu"		Glibc Search vendor "Gnu" for product "Glibc"				>= 2.29 <= 2.33 Search vendor "Gnu" for product "Glibc" and version " >= 2.29 <= 2.33"		-		Affected
Fedoraproject Search vendor "Fedoraproject"		Fedora Search vendor "Fedoraproject" for product "Fedora"				33 Search vendor "Fedoraproject" for product "Fedora" and version "33"		-		Affected
Fedoraproject Search vendor "Fedoraproject"		Fedora Search vendor "Fedoraproject" for product "Fedora"				34 Search vendor "Fedoraproject" for product "Fedora" and version "34"		-		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