Cyber Resilience

CVE-2021-39839

High

Published: 29 September 2021

Published
29 September 2021
Modified
21 November 2024
KEV Added
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Patch
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CVSS Score v3 7.8 CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS Score 0.4546 97.7th percentile
Risk Priority 43 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-39839 is a high-severity Use After Free (CWE-416) vulnerability in Apple Macos. Its CVSS base score is 7.8 (High).

Operationally, ranked in the top 2.3% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

Acrobat Reader DC versions 2021.005.20060 (and earlier), 2020.004.30006 (and earlier) and 2017.011.30199 (and earlier) are affected by a use-after-free vulnerability in the processing of the AcroForm getItem action that could result in arbitrary code execution in the context of the…

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current user. Exploitation of this issue requires user interaction in that a victim must open a malicious file.

CWE(s)
CWE-416

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

adobe
acrobat
20.001.30005 — 20.004.30006 · 17.011.30059 — 17.011.30199
adobe
acrobat reader
20.001.30005 — 20.004.30006 · 17.011.30059 — 17.011.30199
adobe
acrobat dc
15.008.20082 — 21.005.20058 · 15.008.20082 — 21.005.20060
adobe
acrobat reader dc
15.008.20082 — 21.005.20058 · 15.008.20082 — 21.005.20060

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

SI-16 Memory Protection
addresses: CWE-416

Use-after-free exploits that achieve arbitrary code execution are blocked or significantly hardened by non-executable pages and ASLR.

References