CVE-2021-40420 json
A use-after-free vulnerability exists in the JavaScript engine of Foxit Software’s PDF Reader, version 11.1.0.52543.
published 2022-02-04 4 y ago modified 2026-06-17 4 mo ago also EUVD-2021-27597
- cvss
- 8.8
- version 3.0, 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
A use-after-free vulnerability exists in the JavaScript engine of Foxit Software’s PDF Reader, version 11.1.0.52543. A specially-crafted PDF document can trigger the reuse of previously freed memory, which can lead to arbitrary code execution. An attacker needs to trick the user to open the malicious file to trigger this vulnerability. Exploitation is also possible if a user visits a specially-crafted, malicious site if the browser plugin extension is enabled.
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- total
- Assessed
- 18 mo ago
Exploit prediction
4.69% chance of exploitation in the next 30 days, higher than 91% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- talosintelligence.com https://talosintelligence.com/vulnerability_reports/TALOS-2021-1429 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.0 | 8.8 | CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H |
| NVD | 3.1 | 8.8 | CVSS:3.1/AV:N/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
- n/a Foxit
Classification
- Weakness
-
- CWE-416 Use After Free
References
-
talosintelligence.com
/vulnerability_reports/TALOS-2021-1429
exploit, technical-description, third-party-advisory
Sources
- CVE List CVE-2021-40420
- NVD CVE-2021-40420
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