CVE-2026-46033crypto: authencesn - reject short ahash digests during instance creation
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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.
- CVSS
- 7.1 HIGH (v3.1, CISA ADP)CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
- Weakness (CWE)
- CWE-1284
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- Linux
- NVD analysis
- Modified
- Record last updated
- Oct 15, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
Linux Linux linux:linux (from the name) | from f15f05b0a5de667c821a9727c33bce9d1d9b26dd before 77f59fb2d3aa33e90ec6cbbf45dcfb20ab82b1a9; from f15f05b0a5de667c821a9727c33bce9d1d9b26dd before 2f31cd1e64a079c845bca31d2da7b3c90a311726; from f15f05b0a5de667c821a9727c33bce9d1d9b26dd before d4c6a6d08e70bb1083c7c405fc7faacbf19aebc0; from f15f05b0a5de667c821a9727c33bce9d1d9b26dd before b69933e97efea238ebbfcf70c2b1be1cd03f13e3; from f15f05b0a5de667c821a9727c33bce9d1d9b26dd before 67f1f0933cc3d78dde222842bcad2778ec7a0b88; from f15f05b0a5de667c821a9727c33bce9d1d9b26dd before b42821c15445f93daea3e76ada682b2b7181c476; from f15f05b0a5de667c821a9727c33bce9d1d9b26dd before 9aff81e8217e9de2929084b03b3c7f81988c112b; from f15f05b0a5de667c821a9727c33bce9d1d9b26dd before 5db6ef9847717329f12c5ea8aba7e9f588a980c0 | CNA record |
Red Hat Red Hat Enterprise Linux 10 redhat:enterprise_linux | 10 | CISA ADP |
Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP siemens:simatic_s7_1500_cpu_1518_4_pn_dp_mfp (from the name) | from V3.1.6 | CISA ADP |
Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP siemens:simatic_s7_1500_cpu_1518f_4_pn_dp_mfp (from the name) | from V3.1.6 | CISA ADP |
Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem siemens:simatic_s7_1500_tm_mfp_gnu_linux_subsystem (from the name) | all versions | CISA ADP |
Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP siemens:siplus_s7_1500_cpu_1518_4_pn_dp_mfp (from the name) | from V3.1.6 | CISA ADP |
linux linux_kernel linux:linux_kernel | from 4.11 before 5.10.258; from 5.11 before 5.15.209; from 5.16 before 6.1.175; from 6.2 before 6.6.140; from 6.7 before 6.12.86; from 6.13 before 6.18.27; from 6.19 before 7.0.4; 7.1 | NVD |
References
- https://git.kernel.org/stable/c/77f59fb2d3aa33e90ec6cbbf45dcfb20ab82b1a9patch
- https://git.kernel.org/stable/c/2f31cd1e64a079c845bca31d2da7b3c90a311726patch
- https://git.kernel.org/stable/c/d4c6a6d08e70bb1083c7c405fc7faacbf19aebc0patch
- https://git.kernel.org/stable/c/b69933e97efea238ebbfcf70c2b1be1cd03f13e3patch
- https://git.kernel.org/stable/c/67f1f0933cc3d78dde222842bcad2778ec7a0b88patch
- https://git.kernel.org/stable/c/b42821c15445f93daea3e76ada682b2b7181c476patch
- https://git.kernel.org/stable/c/9aff81e8217e9de2929084b03b3c7f81988c112bpatch
- https://git.kernel.org/stable/c/5db6ef9847717329f12c5ea8aba7e9f588a980c0patch
- https://access.redhat.com/security/cve/CVE-2026-46033
- https://bugzilla.redhat.com/show_bug.cgi?id=2482000
- https://cert-portal.siemens.com/productcert/html/ssa-019113.html
- https://cert-portal.siemens.com/productcert/html/ssa-457936.html
- https://cert-portal.siemens.com/productcert/html/ssa-784472.html
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-46033.json
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.