CVE-2021-21086 json
Adobe Reader CoolType Arbitrary Stack Manipulation
published 2021-09-02 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-8477
- cvss
- 7.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 4.7%
- EPSS 4.7% chance of exploitation in 30 days, percentile 91%
- public exploits
- 0
- none known
Summary
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.
Exploit prediction
4.71% chance of exploitation in the next 30 days, higher than 91% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.8 | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H |
| NVD | 3.1 | 7.8 | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H |
| NVD | 2.0 | 6.8 | AV:N/AC:M/Au:N/C:P/I:P/A:P |
Affected products
- Adobe Acrobat Reader
Classification
- Weakness
-
- CWE-787 Out-of-bounds Write
References
-
helpx.adobe.com
/security/products/acrobat/apsb21-09.html
vendor-advisory
Sources
- CVE List CVE-2021-21086
- NVD CVE-2021-21086
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