NTLMv2 credential disclosure via src parameter
Published Sep 29, 2021 · Updated Sep 16, 2024
Information disclosure in Adobe Acrobat Reader DC through 2021.005.20060 allows remote attackers to obtain NTLMv2 credentials via crafted files or web pages. The ActiveX control processes an attacker-supplied src parameter and triggers outbound Windows authentication, disclosing the victim's NTLMv2 challenge response to the attacker. Exploitation requires the victim to open a malicious Microsoft Office file or visit an attacker-controlled web page; the documented impact is credential disclosure without integrity or availability impact.
Summary
What happened
Information disclosure in Adobe Acrobat Reader DC through 2021.005.20060 allows remote attackers to obtain NTLMv2 credentials via crafted files or web pages. The ActiveX control processes an attacker-supplied src parameter and triggers outbound Windows authentication, disclosing the victim's NTLMv2 challenge response to the attacker. Exploitation requires the victim to open a malicious Microsoft Office file or visit an attacker-controlled web page; the documented impact is credential disclosure without integrity or availability impact.
The record
- CVE
- CVE-2021-39855
- Published
- Sep 29, 2021
- Updated
- Sep 16, 2024
- Vendor
- Adobe
- Product
- Adobe Acrobat Reader
- Classifications
- CWE-200, T1187
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Sep 29, 2021CVE publishedPublication date reported by the CVE source.
- Sep 16, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=unspecified <=2017.011.30199
- Affected versionversion=unspecified <=2020.004.30006
- Affected versionversion=unspecified <=2021.005.20060
- Affected versionversion=unspecified <=None
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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