CVE-2023-4421

The NSS code used for checking PKCS#1 v1.5 was leaking information useful in mounting Bleichenbacher-like attacks. Both the overall correctness of the padding as well as the length of the encrypted message was leaking through timing side-channel. By sending large number of attacker-selected ciphertexts, the attacker would be able to decrypt a previously intercepted PKCS#1 v1.5 ciphertext (for example, to decrypt a TLS session that used RSA key exchange), or forge a signature using the victim's key. The issue was fixed by implementing the implicit rejection algorithm, in which the NSS returns a deterministic random message in case invalid padding is detected, as proposed in the Marvin Attack paper. This vulnerability affects NSS < 3.61.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://bugzilla.mozilla.org/show_bug.cgi?id=1651411	Issue Tracking
https://www.mozilla.org/security/advisories/mfsa2023-53/	Issue Tracking Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:mozilla:nss:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2023-12-12 17:15

Updated : 2023-12-20 18:40

NVD link : CVE-2023-4421

Mitre link : CVE-2023-4421

CVE.ORG link : CVE-2023-4421

JSON object : View

Products Affected

mozilla

nss

CWE

CWE-203

Observable Discrepancy

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