CVE-2021-28550 Adobe Acrobat and Reader Use-After-Free

What is CVE-2021-28550?

CVE-2021-28550 is a critical use after free vulnerability in Adobe Acrobat, published on 2 Sep 2021. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

Official description

Acrobat Reader DC versions versions 2021.001.20150 (and earlier), 2020.001.30020 (and earlier) and 2017.011.30194 (and earlier) are affected by a Use After Free vulnerability. An unauthenticated attacker could leverage this vulnerability to achieve arbitrary code execution in the context of the current user. Exploitation of this issue requires user interaction in that a victim must open a malicious file.

Weakness: CWE-416

Which versions are affected by CVE-2021-28550?

It affects 4 products.

Products include Adobe Acrobat, Adobe Acrobat Dc, Adobe Acrobat Reader, Adobe Acrobat Reader Dc.

How do I fix CVE-2021-28550?

No fix has been published for CVE-2021-28550 yet. Limit exposure of the affected software until one is available. US federal agencies must fix it by 17 Nov 2021.

Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.

Is CVE-2021-28550 being exploited?

Yes. Attackers have exploited CVE-2021-28550 in the wild since at least 3 Nov 2021.

Other vulnerabilities in Adobe Acrobat

• CVE-2021-21017 Adobe Acrobat and Reader Heap-based Buffer Overflow Exploited High 8.8
• CVE-2014-0546 Adobe Reader and Acrobat Sandbox Bypass Exploited High 8.8
• CVE-2014-0496 Adobe Reader and Acrobat Use-After-Free Exploited High 8.8
• CVE-2013-3346 Adobe Reader and Acrobat Memory Corruption Exploited High 8.8
• CVE-2013-2729 Adobe Reader and Acrobat Arbitrary Integer Overflow Exploited High 8.8

All Adobe Acrobat vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-865h-4rjv-52pg.