Unknown

CVE-2023-53702 — s390/crypto: use vector instructions only if available for ChaCha20

In the Linux kernel, the following vulnerability has been resolved: s390/crypto: use vector instructions only if available for ChaCha20 Commit 349d03ffd5f6 ("crypto: s390 - add crypto library interface for ChaCha20") added a library interface to the s390 specific ChaCha20 implementation. However no check was added to verify if the required facilities are installed before branching into the assembler code. If compiled into the kernel, this will lead to the following crash, if vector instructions are not available: data exception: 0007 ilc:3 [#1] SMP Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.3.0-rc7+ #11 Hardware name: IBM 3931 A01 704 (KVM/Linux) Krnl PSW : 0704e00180000000 000000001857277a (chacha20_vx+0x32/0x818) R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3 Krnl GPRS: 0000037f0000000a ffffffffffffff60 000000008184b000 0000000019f5c8e6 0000000000000109 0000037fffb13c58 0000037fffb13c78 0000000019bb1780 0000037fffb13c58 0000000019f5c8e6 000000008184b000 0000000000000109 00000000802d8000 0000000000000109 0000000018571ebc 0000037fffb13718 Krnl Code: 000000001857276a: c07000b1f80b larl %r7,0000000019bb1780 0000000018572770: a708000a lhi %r0,10 #0000000018572774: e78950000c36 vlm %v24,%v25,0(%r5),0 >000000001857277a: e7a060000806 vl %v26,0(%r6),0 0000000018572780: e7bf70004c36 vlm %v27,%v31,0(%r7),4 0000000018572786: e70b00000456 vlr %v0,%v27 000000001857278c: e71800000456 vlr %v1,%v24 0000000018572792: e74b00000456 vlr %v4,%v27 Call Trace: [<000000001857277a>] chacha20_vx+0x32/0x818 Last Breaking-Event-Address: [<0000000018571eb6>] chacha20_crypt_s390.constprop.0+0x6e/0xd8 ---[ end trace 0000000000000000 ]--- Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b Fix this by adding a missing MACHINE_HAS_VX check. [agordeev@linux.ibm.com: remove duplicates in commit message]

Published Oct 22, 2025 · Updated Oct 13, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: Linux

Low

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.

How the score was calculated

EPSS 0.2% (30-day exploitation probability)+2

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation

Not confirmed

Not in CISA KEV — an absence of record, not proof it is unexploited.

EPSS FIRST

0.21%

ahead of 11% of scored CVEs · Oct 14, 2026

Affects

Linux

CVSS base

—

Score not published yet.

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

Identify exposed assets running the affected vendor/product/version combinations (Linux Linux).
No fix documented in the sources: reduce exposure and monitor the vendor advisory.
Search available logs for exploit probes, errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Vendor	Product	Versions	Status	Source
Linux	Linux	≥ 349d03ffd5f62c298fd667ffa397c3fdc5c6194b and < 25e8d30507aa2f251152df1af7809e85b5538f4a≥ 349d03ffd5f62c298fd667ffa397c3fdc5c6194b and < debb7797bba0caffdbdadc3e7968bb2c414f50da≥ 349d03ffd5f62c298fd667ffa397c3fdc5c6194b and < 8703dd6b238da0ec6c276e53836f8200983d3d9bversion 5.19	Vulnerable	CVE Program (cve.org) e CISA ADP

EPSS over time FIRST

Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.21%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

Not enough vector or weakness data: use the affected application’s logs as a starting point.

application logs

Timeline

What happened to this CVE, newest first.

2026
Record published
Oct 13, 2026
Affected products added · linux/linux
Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
Source status changed · → Deferred
Oct 13, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 13, 2026 · NIST National Vulnerability Database
2025
CVE published
Oct 22, 2025 · Linux

Source activity

Repeated readings are counted rather than listed.

1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

3 on the record

git.kernel.org/stable/c/debb7797bba0caffdbdadc3e7968bb2c414f50da
NIST National Vulnerability Database
git.kernel.org/stable/c/8703dd6b238da0ec6c276e53836f8200983d3d9b
NIST National Vulnerability Database
git.kernel.org/stable/c/25e8d30507aa2f251152df1af7809e85b5538f4a
NIST National Vulnerability Database

Elsewhere on this site

Linux
every CVE for this vendor

Related CVEs (same products)

Critical CVE-2026-99999 ipv4: validate checksum_start before completing checksum 9h
Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 9h
Unknown CVE-2026-98424 wifi: cfg80211: undo netns switch if renaming the wiphy fails 1d
Unknown CVE-2026-98425 wifi: mac80211: don't warn when an IBSS has no channel to scan 1d
Unknown CVE-2026-98426 wifi: mwifiex: fix IRQ leak using wrong index in MSI-X error path 1d
Unknown CVE-2026-98427 net/sched: codel: bound the dropping loop per dequeue call 1d

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No CVSS score published by NVD, the CNA, CISA or GitHub so far.
No fixed version, patch or mitigation documented.
No CISA SSVC assessment.
No CWE classification.
No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2023-53702 is "s390/crypto: use vector instructions only if available for ChaCha20", rated Unknown. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. EPSS 0.21% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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