#VU27988 Out-of-bounds write in FreeRDP - CVE-2020-11521

Vulnerability identifier: #VU27988

Vulnerability risk: High

CVSSv4.0: 8.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2020-11521

CWE-ID: CWE-787

Exploitation vector: Network

Exploit availability: No

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

Vendor: FreeRDP

Description

The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists due to a boundary error when processing untrusted input in "libfreerdp/codec/planar.c". A remote attacker can trigger out-of-bounds write and execute arbitrary code on the target system.

Note: This vulnerability affects versions greater than 1.0

Mitigation
Install updates from vendor's website.

Vulnerable software versions

FreeRDP: 2.0.0 rc4

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External links
https://github.com/FreeRDP/FreeRDP/commits/master
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-5cwc-6wc9-255w
https://pub.freerdp.com/cve/CVE-2020-11521/pocAnalysis_6.pdf

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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.