CVE-2021-39855 json
Adobe Acrobat Reader DC NTLMv2 SSO Information Disclosure via src Parameter
published 2021-09-29 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-26212
- cvss
- 6.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 2.4%
- EPSS 2.4% chance of exploitation in 30 days, percentile 83%
- public exploits
- 0
- none known
Summary
Acrobat Reader DC ActiveX Control versions 2021.005.20060 (and earlier), 2020.004.30006 (and earlier) and 2017.011.30199 (and earlier) are affected by an Information Disclosure vulnerability. An unauthenticated attacker could leverage this vulnerability to obtain NTLMv2 credentials. Exploitation of this issue requires user interaction in that a victim must open a maliciously crafted Microsoft Office file, or visit an attacker controlled web page.
Exploit prediction
2.36% chance of exploitation in the next 30 days, higher than 83% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N |
| NVD | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N |
| NVD | 2.0 | 4.3 | AV:N/AC:M/Au:N/C:P/I:N/A:N |
Affected products
- Adobe Acrobat Reader
Classification
- Weakness
-
- CWE-200 Exposure of Sensitive Information to an Unauthorized Actor
References
-
helpx.adobe.com
/security/products/acrobat/apsb21-55.html
release-notes, vendor-advisory
Sources
- CVE List CVE-2021-39855
- NVD CVE-2021-39855
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