CVE-2025-52473
Description
An observable discrepancy was found in the reference implementation of the HQC key encapsulation mechanism when it is compiled with Clang for optimization levels above -O0 onto -O1, -O2, and beyond. A proof-of-concept local attack exploits this secret-dependent information to recover the entire secret key.
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 5.9 | 5.5 | N/A |
| Attack Vector | Network | Local | N/A |
| Attack Complexity | High | Low | N/A |
| Privileges Required | None | Low | N/A |
| User Interaction | None | None | N/A |
| Scope | Unchanged | Unchanged | N/A |
| Confidentiality | High | High | N/A |
| Integrity Impact | None | None | N/A |
| Availability Impact | None | None | N/A |
Vector
Red Hat: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
NVD: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Understanding the Weakness (CWE)
Confidentiality,Access Control
Technical Impact: Read Application Data; Bypass Protection Mechanism
An attacker can gain access to sensitive information about the system, including authentication information that may allow an attacker to gain access to the system. Other security-relevant information about the operation or internal state of the product may be revealed to an unauthorized actor, such as whether a particular operation was successful or not.
Confidentiality
Technical Impact: Read Application Data
In some cases, discrepancies can be used by attackers to form a side channel. When cryptographic primitives are vulnerable to side-channel attacks, this could be used to reveal unencrypted plaintext in the worst case.
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