Cisco ClamAV up to 8.4.5.30483 XAR File Format Parser memory corruption

Summaryinfo

A vulnerability has been found in Cisco ClamAV and classified as critical. Affected by this issue is some unknown functionality of the component XAR File Format Parser. The manipulation leads to memory corruption. This vulnerability is uniquely identified as CVE-2026-20348. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Cisco ClamAV. This issue affects an unknown part of the component XAR File Format Parser. The manipulation with an unknown input leads to a memory corruption vulnerability. Using CWE to declare the problem leads to CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. Impacted is availability. The summary by CVE is:

A vulnerability in the XAR file format parser of ClamAV could allow an unauthenticated, remote attacker to cause a DoS condition or possibly other expanded impacts as a result of memory corruption on an affected device. This vulnerability is due to improper boundary checks for content in XAR files during scanning. An attacker could exploit this vulnerability by submitting a crafted file that contains XAR content to be scanned by ClamAV on an affected device. A successful exploit could allow the attacker to cause the ClamAV scanning process to terminate, resulting in a DoS condition on the affected software.

It is possible to read the advisory at sec.cloudapps.cisco.com. The identification of this vulnerability is CVE-2026-20348 since 10/08/2025. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 08/07/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-54508). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

• Anti-Malware Software

Vendor

• Cisco

Name

• ClamAV

Version

• 1.6.0
• 1.7.0
• 1.8.0
• 1.8.1
• 1.8.4
• 1.9.0
• 1.9.1
• 1.10.0
• 1.10.1
• 1.10.2
• 1.11.0
• 1.11.1
• 1.12.0
• 1.12.1
• 1.12.2
• 1.12.3
• 1.12.4
• 1.12.5
• 1.12.6
• 1.12.7
• 1.13.0
• 1.13.1
• 1.13.2
• 1.14.0
• 1.14.1
• 1.15.0
• 1.15.1
• 1.15.2
• 1.15.3
• 1.15.4
• 1.15.5
• 1.15.6
• 1.16.0
• 1.16.1
• 1.16.2
• 1.16.3
• 1.17.0
• 1.17.1
• 1.17.2
• 1.18.0
• 1.18.1
• 1.19.0
• 1.20.0
• 1.20.1
• 1.20.2
• 1.20.3
• 1.20.4
• 1.20.5
• 1.20.6
• 1.20.7
• 1.20.8
• 1.21.0
• 1.21.1
• 1.21.2
• 1.21.3
• 1.22.0
• 1.22.1
• 1.22.2
• 1.22.3
• 1.22.4
• 1.23.0
• 1.23.1
• 1.24.0
• 1.24.1
• 1.24.2
• 1.24.3
• 1.24.4
• 1.24.5
• 1.25.0
• 1.25.1
• 1.25.2
• 1.26.0
• 1.26.1
• 1.27.0
• 1.27.1
• 1.27.2
• 6.0.7
• 6.0.9
• 6.1.5
• 6.1.7
• 6.1.9
• 6.2.1
• 6.2.3
• 6.2.5
• 6.2.9
• 6.2.19
• 6.3.1
• 6.3.3
• 6.3.5
• 6.3.7
• 7.0.5
• 7.1.1
• 7.1.5
• 7.2.3
• 7.2.5
• 7.2.7
• 7.2.11
• 7.2.13
• 7.3.1
• 7.3.3
• 7.3.5
• 7.3.9
• 7.3.13
• 7.3.15
• 7.4.1
• 7.4.1.20425
• 7.4.1.20439
• 7.4.3
• 7.4.3.20679
• 7.4.5
• 7.5.1.20813
• 7.5.1.20833
• 7.5.3
• 7.5.5
• 7.5.7
• 7.5.9
• 7.5.11
• 7.5.13.21586
• 7.5.13.21598
• 7.5.15.21611
• 7.5.17.21680
• 7.5.19
• 7.5.20
• 7.5.21.21732
• 8.0.1.21160
• 8.0.1.21164
• 8.1.3
• 8.1.3.21242
• 8.1.5
• 8.1.5.21322
• 8.1.7
• 8.1.7.21417
• 8.1.7.21512
• 8.1.7.21585
• 8.2.1.21612
• 8.2.1.21650
• 8.2.3.30119
• 8.2.4.30130
• 8.4.0
• 8.4.1.30298
• 8.4.1.30307
• 8.4.2.30317
• 8.4.3
• 8.4.4.30419
• 8.4.4.30467
• 8.4.5.30483

License

• free

Website

• Vendor: https://www.cisco.com/

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Entryinfo

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