CVE-2021-39855

Adobe Acrobat Reader DC NTLMv2 SSO Information Disclosure via src Parameter

MEDIUM
6.5
CVSS Score
Published: September 29, 2021 at 03:39 PM UTC
Updated: June 17, 2026 at 04:04 AM UTC
3 products affected across 1 vendorAcrobat ReaderAcrobatAcrobat DC· also runs on 2 platforms

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Severity
MEDIUM6.5
Exploit prediction
EPSS 2%

Description

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

17.011.30059 ≤ v ≤ 17.011.3019920.001.30005 ≤ v ≤ 20.004.30006
apple-macos (environment) · microsoft-windows (environment)
15.008.20082 ≤ v ≤ 21.005.2005815.008.20082 ≤ v ≤ 21.005.20060
apple-macos (environment) · microsoft-windows (environment)
v ≤ 2017.011.30199v ≤ 2020.004.30006v ≤ 2021.005.2006017.011.30059 ≤ v ≤ 17.011.3019920.001.30005 ≤ v ≤ 20.004.30006
apple-macos (environment) · microsoft-windows (environment)

Runs on — not affected

The affected product only carries this flaw when running on these platforms. The platforms themselves are not vulnerable.

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (1)

CVSS

6.5MEDIUMadobe
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
NONE
Availability
NONE
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-200

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