Vulnerability · Published Sep 2, 2021 · Assigned by adobe

CVE-2021-21086Adobe Reader CoolType Arbitrary Stack Manipulation

High 7.8

In plain English

A high-severity out-of-bounds write in Acrobat Reader from Adobe. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 4.7% (higher than 92% of all known vulnerabilities). Ready-made attack tooling exists: public proof-of-concept code.

Severity (CVSS 3.1)7.8High

Exploit odds (30 days)4.7%top 8.1% of all CVEs

Exploited in the wildNo reportsnot in CISA KEV

Attack tooling1Public PoC

Official description

Acrobat Reader DC versions versions 2020.013.20074 (and earlier), 2020.001.30018 (and earlier) and 2017.011.30188 (and earlier) are affected by an Out-of-bounds Write vulnerability in the CoolType library. 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.

Affected products (as reported)

Vendor	Product	Versions
Adobe	Acrobat Reader	unspecified – through 2020.013.20074unspecified – through 2020.001.30018unspecified – through 2017.011.30188unspecified – through None

Weakness: CWE-787 · Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

References

https://helpx.adobe.com/security/products/acrobat/apsb21-09.html x_refsource_MISC