CVE-2021-40528

  1. OpenCVE
  2. Vulnerabilities (CVE)
  3. 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.

5.9 /10

CVSS v3 : MEDIUM

V3 Legend

Vector :

Exploitability : 2.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

2.6 /10

CVSS v2.0 : LOW

V2 Legend

Vector : AV:N/AC:H/Au:N/C:P/I:N/A:N

Exploitability : 4.9 / Impact : 2.9

Access Vector NETWORK

Access Complexity HIGH

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact NONE

Availability Impact NONE

References
Link Resource
https://eprint.iacr.org/2021/923 Technical Description Third Party Advisory
https://git.gnupg.org/cgi-bin/gitweb.cgi?p=libgcrypt.git%3Ba=commit%3Bh=3462280f2e23e16adf3ed5176e0f2413d8861320
https://ibm.github.io/system-security-research-updates/2021/07/20/insecurity-elgamal-pt1 Third Party Advisory
https://ibm.github.io/system-security-research-updates/2021/09/06/insecurity-elgamal-pt2 Exploit Third Party Advisory
https://security.gentoo.org/glsa/202210-13 Third Party Advisory
https://eprint.iacr.org/2021/923 Technical Description Third Party Advisory
https://git.gnupg.org/cgi-bin/gitweb.cgi?p=libgcrypt.git%3Ba=commit%3Bh=3462280f2e23e16adf3ed5176e0f2413d8861320
https://ibm.github.io/system-security-research-updates/2021/07/20/insecurity-elgamal-pt1 Third Party Advisory
https://ibm.github.io/system-security-research-updates/2021/09/06/insecurity-elgamal-pt2 Exploit Third Party Advisory
https://security.gentoo.org/glsa/202210-13 Third Party Advisory
Configurations

Configuration 1 (hide)

cpe:2.3:a:gnupg:libgcrypt:*:*:*:*:*:*:*:*
History

21 Nov 2024, 06:24

Type Values Removed Values Added
References () https://eprint.iacr.org/2021/923 - Technical Description, Third Party Advisory () https://eprint.iacr.org/2021/923 - Technical Description, Third Party Advisory
References () https://git.gnupg.org/cgi-bin/gitweb.cgi?p=libgcrypt.git%3Ba=commit%3Bh=3462280f2e23e16adf3ed5176e0f2413d8861320 - () https://git.gnupg.org/cgi-bin/gitweb.cgi?p=libgcrypt.git%3Ba=commit%3Bh=3462280f2e23e16adf3ed5176e0f2413d8861320 -
References () https://ibm.github.io/system-security-research-updates/2021/07/20/insecurity-elgamal-pt1 - Third Party Advisory () https://ibm.github.io/system-security-research-updates/2021/07/20/insecurity-elgamal-pt1 - Third Party Advisory
References () https://ibm.github.io/system-security-research-updates/2021/09/06/insecurity-elgamal-pt2 - Exploit, Third Party Advisory () https://ibm.github.io/system-security-research-updates/2021/09/06/insecurity-elgamal-pt2 - Exploit, Third Party Advisory
References () https://security.gentoo.org/glsa/202210-13 - Third Party Advisory () https://security.gentoo.org/glsa/202210-13 - Third Party Advisory

31 Oct 2022, 04:15

Type Values Removed Values Added
References
  • (GENTOO) https://security.gentoo.org/glsa/202210-13 -

29 Nov 2021, 21:37

Type Values Removed Values Added
References (MISC) https://git.gnupg.org/cgi-bin/gitweb.cgi?p=libgcrypt.git;a=commit;h=3462280f2e23e16adf3ed5176e0f2413d8861320 - (MISC) https://git.gnupg.org/cgi-bin/gitweb.cgi?p=libgcrypt.git;a=commit;h=3462280f2e23e16adf3ed5176e0f2413d8861320 - Mailing List, Patch, Third Party Advisory

17 Nov 2021, 07:15

Type Values Removed Values Added
References
  • (MISC) https://git.gnupg.org/cgi-bin/gitweb.cgi?p=libgcrypt.git;a=commit;h=3462280f2e23e16adf3ed5176e0f2413d8861320 -

13 Sep 2021, 16:22

Type Values Removed Values Added
References (MISC) https://ibm.github.io/system-security-research-updates/2021/07/20/insecurity-elgamal-pt1 - (MISC) https://ibm.github.io/system-security-research-updates/2021/07/20/insecurity-elgamal-pt1 - Third Party Advisory
References (MISC) https://ibm.github.io/system-security-research-updates/2021/09/06/insecurity-elgamal-pt2 - (MISC) https://ibm.github.io/system-security-research-updates/2021/09/06/insecurity-elgamal-pt2 - Exploit, Third Party Advisory
References (MISC) https://eprint.iacr.org/2021/923 - (MISC) https://eprint.iacr.org/2021/923 - Technical Description, Third Party Advisory
CPE cpe:2.3:a:gnupg:libgcrypt:*:*:*:*:*:*:*:*
CVSS v2 : unknown
v3 : unknown 		v2 : 2.6
v3 : 5.9
CWE CWE-327

06 Sep 2021, 19:15

Type Values Removed Values Added
New CVE
Information

Published : 2021-09-06 19:15

Updated : 2024-11-21 06:24

NVD link : CVE-2021-40528

Mitre link : CVE-2021-40528

CVE.ORG link : CVE-2021-40528

JSON object : View

Products Affected

gnupg

  • libgcrypt
CWE
CWE-327

Use of a Broken or Risky Cryptographic Algorithm