Vulnerability Details : CVE-2021-40528
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.
Exploit prediction scoring system (EPSS) score for CVE-2021-40528
Probability of exploitation activity in the next 30 days: 0.14%
Percentile, the proportion of vulnerabilities that are scored at or less: ~ 49 % EPSS Score History EPSS FAQ
CVSS scores for CVE-2021-40528
| Base Score | Base Severity | CVSS Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|
|
2.6
|
LOW | AV:N/AC:H/Au:N/C:P/I:N/A:N |
4.9
|
2.9
|
[email protected] |
|
5.9
|
MEDIUM | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N |
2.2
|
3.6
|
[email protected] |
CWE ids for CVE-2021-40528
-
The product uses a broken or risky cryptographic algorithm or protocol.Assigned by: [email protected] (Primary)
References for CVE-2021-40528
-
https://ibm.github.io/system-security-research-updates/2021/09/06/insecurity-elgamal-pt2
Exploit;Third Party Advisory
-
https://eprint.iacr.org/2021/923
Technical Description;Third Party Advisory
-
https://ibm.github.io/system-security-research-updates/2021/07/20/insecurity-elgamal-pt1
Third Party Advisory
-
https://security.gentoo.org/glsa/202210-13
Third Party Advisory
-
https://git.gnupg.org/cgi-bin/gitweb.cgi?p=libgcrypt.git;a=commit;h=3462280f2e23e16adf3ed5176e0f2413d8861320
Mailing List;Patch;Third Party Advisory
Products affected by CVE-2021-40528
- cpe:2.3:a:gnupg:libgcrypt:*:*:*:*:*:*:*:*