CVE-2021-40529

The ElGamal implementation in Botan through 2.18.1, as used in Thunderbird and other products, 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.

CVSS v3.0 5.9 MEDIUM
CVSS v2.0 2.6 LOW

5.9^/10

CVSS v3.0 : MEDIUM

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

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://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://github.com/randombit/botan/pull/2790	Patch Third Party Advisory
https://eprint.iacr.org/2021/923	Technical Description Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/UPHGYWNJQKWLTUWBNSFB4F66MQDIL3IB/	Mailing List Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/72NB4OLD3VHJC3YF3PEP2HKF6BYURPAO/	Mailing List Third Party Advisory
https://security.gentoo.org/glsa/202208-14	Third Party Advisory

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Configurations

Configuration 1 (hide)

cpe:2.3:a:botan_project:botan:*:*:*:*:*:*:*:*

Configuration 2 (hide)

OR	cpe:2.3:o:fedoraproject:fedora:34:::::::*
	cpe:2.3:o:fedoraproject:fedora:35:::::::*

Configuration 3 (hide)

cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*

Information

Published : 2021-09-06 12:15

Updated : 2022-12-09 07:24

NVD link : CVE-2021-40529

Mitre link : CVE-2021-40529

JSON object : View

CWE

CWE-327

Use of a Broken or Risky Cryptographic Algorithm

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Products Affected

mozilla

thunderbird

fedoraproject

fedora

botan_project

botan

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