GHSA-q29p-9pfr-j652 — high GitHub Advisory in rust/libcrux-sha3

Description

The incremental squeeze functions in the portable SHAKE XOF API, when attempting to squeeze more than RATE (168 for SHAKE128, 136 for SHAKE256) bytes, performed an additional permutation of the state before producing the first output block, thus discarding the first block of RATE bytes of valid XOF output.

Impact

This bug impacts users that rely on this XOF API to squeeze more than RATE bytes. It does not impact the use of libcrux-sha3 in libcrux-ml-kem or libcrux-ml-dsa.

Mitigation

Starting from version 0.0.8 the squeeze functions correctly output all blocks including the first block.

Basic information

Type: reviewed
Severity: high
Advisory on GitHub: Open advisory ↗
Repository advisory: —
Source code: Browse source ↗
Published (advisory): 2026-03-26 17:59:34 UTC
Updated: 2026-03-26 17:59:35 UTC
GitHub reviewed: 2026-03-26 17:59:34 UTC

CVSS Scores

Base score	Version	Severity	Vector
8.7	4.0	—	`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N` Click to expand Attack vector (AV:N) Could be attacked over the internet or any normal routed network. Attack complexity (AC:L) Exploitation conditions are straightforward and stable. Attack requirements (AT:N) No additional preconditions are required beyond normal reachability. Privileges required (PR:N) No privileges are required. User interaction (UI:N) No user interaction is required. Vulnerable system confidentiality impact (VC:N) No confidentiality impact on the vulnerable system. Vulnerable system integrity impact (VI:H) High integrity impact on the vulnerable system. Vulnerable system availability impact (VA:N) No availability impact on the vulnerable system. Subsequent system confidentiality impact (SC:N) No confidentiality impact on subsequent systems. Subsequent system integrity impact (SI:N) No integrity impact on subsequent systems. Subsequent system availability impact (SA:N) No availability impact on subsequent systems.

Identifiers

Type	Value
GHSA	GHSA-q29p-9pfr-j652 ↗

CWEs

CWE id	Name
CWE-682	Incorrect Calculation

Affected packages (1)

Vulnerable version ranges and first patched releases as published by GitHub.

Ecosystem	Package	Vulnerable range	First patched	Vulnerable functions
rust	libcrux-sha3	< 0.0.8	0.0.8	—

libcrux-sha3: Incorrect output from SHAKE squeeze functions