#VU57124 Time-of-check Time-of-use (TOCTOU) Race Condition in Cisco AnyConnect Secure Mobility Client - CVE-2021-34788

Vulnerability identifier: #VU57124

Vulnerability risk: Low

CVSSv4.0: 4.4 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-34788

CWE-ID: CWE-367

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
Cisco AnyConnect Secure Mobility Client
Client/Desktop applications / Other client software

Vendor: Cisco Systems, Inc

Description

The vulnerability allows a local user to compromise the target system.

The vulnerability exists due to a race condition in the signature verification process for shared library files that are loaded on an affected device. A local user can send a series of crafted interprocess communication (IPC) messages and execute arbitrary code on the target device with root privileges.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Cisco AnyConnect Secure Mobility Client: before 4.10.03104

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External links
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-anyconnect-lib-hija-cAFB7x4q

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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.