#VU51742 Heap-based buffer overflow in libebml - CVE-2021-3405

Vulnerability identifier: #VU51742

Vulnerability risk: High

CVSSv4.0: 6.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2021-3405

CWE-ID: CWE-122

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
libebml
Other software / Other software solutions

Vendor: www.matroska.org

Description

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to a boundary error in EbmlString::ReadData and EbmlUnicodeString::ReadData in libebml. A remote attacker can pass specially crafted file to the application, trigger heap-based buffer overflow and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

libebml: 1.4.0 - 1.4.1

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External links
https://github.com/Matroska-Org/libebml/issues/74
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/JNHQI6MDOECJ2HT5GCLEX2DMJFEOWPW7/
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/UHIIMWZKHHELFF4NRDMOOCS3HKK3K4DF/
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/YY7R2JZRO5I6WS62KTJFTZGKYELVFTVB/

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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.