CVE-2026-46033

Published May 27, 2026

Last updated 10 days ago

CVSS high 7.1

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: crypto: authencesn - reject short ahash digests during instance creation authencesn requires either a zero authsize or an authsize of at least 4 bytes because the ESN encrypt/decrypt paths always move 4 bytes of high-order sequence number data at the end of the authenticated data. While crypto_authenc_esn_setauthsize() already rejects explicit non-zero authsizes in the range 1..3, crypto_authenc_esn_create() still copied auth->digestsize into inst->alg.maxauthsize without validating it. The AEAD core then initialized the tfm's default authsize from that value. As a result, selecting an ahash with digest size 1..3, such as cbcmac(cipher_null), exposed authencesn instances whose default authsize was invalid even though setauthsize() would have rejected the same value. AF_ALG could then trigger the ESN tail handling with a too-short tag and hit an out-of-bounds access. Reject authencesn instances whose ahash digest size is in the invalid non-zero range 1..3 so that no tfm can inherit an unsupported default authsize.
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Modified
Products
linux_kernel

Risk scores

CVSS 3.1

Type
Primary
Base score
7.1
Impact score
5.2
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
Severity
HIGH

Weaknesses

nvd@nist.gov
CWE-125
0b0ca135-0b70-47e7-9f44-1890c2a1c46c
CWE-1284

Social media

Hype score
Not currently trending

  1. 🪟 Linux kernel crypto bug (CVE-2026-46033) via AF_ALG OOB access… even if it’s “not Windows,” your WSL/VM/container stack still runs Linux. Patch time: crypto ≠ safe. #Windows #Security #WSL #Linux #CVE https://t.co/3bou0wHKJC #LinuxKernel #WslAndContainers #AfAlg #C

    @windowsforum

    28 May 2026

    36 Impressions

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Configurations

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References

Sources include official advisories and independent security research.