CVE-2021-40528
5.9 · MEDIUMOverview
CVE-2021-40528 is a medium-severity vulnerability affecting gnupg libgcrypt. It was published on September 6, 2021 and has a CVSS 3.1 base score of 5.9 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 5.9, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical Description
The ElGamal implementation in Libgcrypt before 1.9.4 allows plaintext recovery because, during interaction between two cryptographic libraries, a certain dangerous combination of the prime defined by the receiver's public key, the generator defined by the receiver's public key, and the sender's ephemeral exponents can lead to a cross-configuration attack against OpenPGP.
Remediation
Check the references section for vendor advisories and patches from gnupg. Update libgcrypt 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 |
|---|---|---|---|
| gnupg | libgcrypt | >= 0, < 1.9.4 | Affected |
References
Frequently Asked Questions
What is CVE-2021-40528?
CVE-2021-40528 is a medium-severity vulnerability affecting gnupg libgcrypt. It was published on September 6, 2021 and has a CVSS 3.1 base score of 5.9 (MEDIUM).
How severe is CVE-2021-40528?
This vulnerability has a CVSS 3.1 base score of 5.9, 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-2021-40528?
Check the references section for vendor advisories and patches from gnupg. Update libgcrypt 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-2021-40528?
CyberStrike's AI-powered security agents can automatically detect CVE-2021-40528 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
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