9.1 CVE-2026-34872

Enriched by CISA
 

An issue was discovered in Mbed TLS 3.5.x and 3.6.x through 3.6.5 and TF-PSA-Crypto 1.0. There is a lack of contributory behavior in FFDH due to improper input validation. Using finite-field Diffie-Hellman, the other party can force the shared secret into a small set of values (lack of contributory behavior). This is a problem for protocols that depend on contributory behavior (which is not the case for TLS). The attack can be carried by the peer, or depending on the protocol by an active network attacker (person in the middle).
https://nvd.nist.gov/vuln/detail/CVE-2026-34872

Categories

CWE-347 : Improper Verification of Cryptographic Signature
The product does not verify, or incorrectly verifies, the cryptographic signature for data. Automated static analysis, commonly referred to as Static Application Security Testing (SAST), can find some instances of this weakness by analyzing source code (or binary/compiled code) without having to execute it. Typically, this is done by building a model of data flow and control flow, then searching for potentially-vulnerable patterns that connect "sources" (origins of input) with "sinks" (destinations where the data interacts with external components, a lower layer such as the OS, etc.) Does not properly verify signatures for "trusted" entities. Insufficient verification allows spoofing. Insufficient verification allows spoofing. Accepts a configuration file without a Message Integrity Check (MIC) signature.

References


 

AFFECTED (from MITRE)


Vendor Product Versions
n/a n/a
  • n/a [affected]
© 2022 The MITRE Corporation. This work is reproduced and distributed with the permission of The MITRE Corporation.

CPE

cpe start end


REMEDIATION




EXPLOITS


Exploit-db.com

id description date
No known exploits

POC Github

Url
No known exploits

Other Nist (github, ...)

Url
No known exploits


CAPEC


Common Attack Pattern Enumerations and Classifications

id description severity
463 Padding Oracle Crypto Attack
High
475 Signature Spoofing by Improper Validation
High