#VU66142 Use-after-free in OpenSC - CVE-2021-42779

Vulnerability identifier: #VU66142

Vulnerability risk: Low

CVSSv4.0: 0.1 [CVSS:4.0/AV:P/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-42779

CWE-ID: CWE-416

Exploitation vector: Local

Exploit availability: No

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

Vendor: OpenSC

Description

The vulnerability allows an attacker with physical access to perform a denial of service attack.

The vulnerability exists due to a use-after-free error in Opensc in sc_file_valid. An attacker with physical access can trigger use-after-free to perform a denial of service attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

OpenSC: 0.2.0 - 0.21.0

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External links
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=28843
https://bugzilla.redhat.com/show_bug.cgi?id=2016086
https://github.com/OpenSC/OpenSC/commit/1db88374

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Q & A

Can this vulnerability be exploited remotely?

No. The attacker should have physical access to the system in order to successfully exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

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