Vulnerability identifier: #VU54559

Vulnerability risk: Low

CVSSv3.1: 3.1 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:U/RL:U/RC:C]

CVE-ID: CVE-2021-27645

CWE-ID: CWE-415

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
Glibc
Universal components / Libraries / Libraries used by multiple products

Vendor: GNU

Description

The vulnerability allows a local user to perform a denial of service (DoS) attack.

The vulnerability exists due to a boundary error within the nameserver caching daemon (nscd) in the GNU C Library when processing a request for netgroup lookup. A local user can initiate a specially crafted request, trigger a double free error and perform a denial of service (DoS) attack.

Mitigation
Cybersecurity Help is currently unaware of any official solution to address this vulnerability.

Vulnerable software versions

Glibc: 2.29.9000 - 2.33.9000

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External links
http://sourceware.org/bugzilla/show_bug.cgi?id=27462
http://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/I7TS26LIZSOBLGJEZMJX4PXT5BQDE2WS/
http://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/7LZNT6KTMCCWPWXEOGSHD3YLYZKUGMH5/

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Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.