CVE-2021-39855
6.5 · MEDIUMOverview
CVE-2021-39855 is a medium-severity vulnerability affecting adobe acrobat. It was published on September 29, 2021 and has a CVSS 3.1 base score of 6.5 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 6.5, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical 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.
Remediation
Check the references section for vendor advisories and patches from adobe. Update acrobat to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| adobe | acrobat | 17.011.30059 | Affected |
| adobe | acrobat_reader | 17.011.30059 | Affected |
| adobe | acrobat_dc | 15.008.20082 | Affected |
| adobe | acrobat_reader_dc | 15.008.20082 | Affected |
Frequently Asked Questions
What is CVE-2021-39855?
CVE-2021-39855 is a medium-severity vulnerability affecting adobe acrobat. It was published on September 29, 2021 and has a CVSS 3.1 base score of 6.5 (MEDIUM).
How severe is CVE-2021-39855?
This vulnerability has a CVSS 3.1 base score of 6.5, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2021-39855?
Check the references section for vendor advisories and patches from adobe. Update acrobat to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2021-39855?
CyberStrike's AI-powered security agents can automatically detect CVE-2021-39855 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
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