RUSTSEC-2026-0331: libcrux-kem

Package	Ecosystem	Affected	Fixed in
libcrux-kem	crates.io	>=0.0.0-0, <0.0.10	0.0.10

Machine-written summary

Summary written by Claude Haiku from the source advisory. Not reviewed by a person.

The libcrux-kem crate, versions before 0.0.10, panics when its decode functions for X25519MlKem768Draft00 private keys, X25519MlKem768Draft00 public keys, and XWingKemDraft06 public keys receive an input shorter than the key type's expected length. An application that decodes attacker-supplied bytes into these key types can be made to crash. Upgrade to libcrux-kem 0.0.10, which returns InvalidPrivateKey or InvalidPublicKey errors for invalid lengths instead.

Written 3 Nov 2026.

Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

Severity and exploitation

Score	Rating	CVSS	Vector	Source
Not published	None	4.0	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N	OSV

CISA KEV Not listed.
EPSS No score.

Timeline

31 Oct 2026, 14:24 UTC First seen by agentprime
31 Oct 2026, 14:24 UTC Confirmed by OSV

Sources

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.