CVE-2021-39856
Last modified
CVE-2021-39856 is a medium-severity vulnerability rated 6.5/10 on the CVSS scale. 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. EPSS estimates a 2.29% chance of exploitation in the next 30 days.
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 visit an attacker controlled web page.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Adobe | Acrobat | >= 17.011.30059, <= 17.011.30199 |
| Adobe | Acrobat Reader | >= 17.011.30059, <= 17.011.30199 |
| Adobe | Acrobat | >= 20.001.30005, <= 20.004.30006 |
| Adobe | Acrobat Reader | >= 20.001.30005, <= 20.004.30006 |
| Adobe | Acrobat Dc | >= 15.008.20082, <= 21.005.20058 |
| Adobe | Acrobat Reader Dc | >= 15.008.20082, <= 21.005.20058 |
| Adobe | Acrobat Dc | >= 15.008.20082, <= 21.005.20060 |
| Adobe | Acrobat Reader Dc | >= 15.008.20082, <= 21.005.20060 |
References
- https://helpx.adobe.com/security/products/acrobat/apsb21-55.htmlRelease Notes, Vendor Advisory
- https://helpx.adobe.com/security/products/acrobat/apsb21-55.htmlRelease Notes, Vendor Advisory
Timeline
- Published
- Last Modified
- Status
- Modified
Frequently Asked Questions
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How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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Related CVEs from 2021
- CVE-2021-39850Acrobat Reader DC versions 2021.005.20060 (and earlier), 202…5.5
- CVE-2021-39851Acrobat Reader DC versions 2021.005.20060 (and earlier), 202…5.5
- CVE-2021-39852Acrobat Reader DC versions 2021.005.20060 (and earlier), 202…5.5
- CVE-2021-39853Acrobat Reader DC versions 2021.005.20060 (and earlier), 202…5.5
- CVE-2021-39854Acrobat Reader DC versions 2021.005.20060 (and earlier), 202…5.5
- CVE-2021-39855Acrobat Reader DC ActiveX Control versions 2021.005.20060 (a…6.5
- CVE-2021-39857Adobe Acrobat Reader DC add-on for Internet Explorer version…4.3
- CVE-2021-39858Acrobat Reader DC versions 2021.005.20060 (and earlier), 202…3.3
- CVE-2021-39859Acrobat Reader DC versions 2021.005.20060 (and earlier), 202…5.5
- CVE-2021-3986A vulnerability in janeczku/calibre-web allows unauthorized …4.3
- CVE-2021-39860Acrobat Pro DC versions 2021.005.20060 (and earlier), 2020.0…5.5
- CVE-2021-39861Acrobat Reader DC versions 2021.005.20060 (and earlier), 202…5.5
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