#VU54560 Use-after-free in Glibc - CVE-2021-33574

Vulnerability identifier: #VU54560

Vulnerability risk: High

CVSSv4.0: 7.2 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2021-33574

CWE-ID: CWE-416

Exploitation vector: Network

Exploit availability: No

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

Vendor: GNU

Description

The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists due to a use-after-free error in the mq_notify() function in the GNU C Library. A remote attacker can force the library to use the notification thread attributes object (passed through its struct sigevent parameter) after it has been freed by the caller, leading to a denial of service or possibly remote code execution.

Successful exploitation of the vulnerability may allow an attacker to compromise vulnerable system.

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

Vulnerable software versions

Glibc: 2.32 - 2.33.9000

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External links
https://sourceware.org/bugzilla/show_bug.cgi?id=27896
https://sourceware.org/bugzilla/show_bug.cgi?id=27896#c1
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/RBUUWUGXVILQXVWEOU7N42ICHPJNAEUP/
https://security.netapp.com/advisory/ntap-20210629-0005/

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

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