VulnerabilityPublished 15 Aug 2026Updated 21 Oct 2026

CVE-2026-74466: Linux kernel · s390/zcrypt: Close speculative mem read possibility

Affects Linux kernelSource CVE Database V5

Not known to be exploited · fixed in e935cd525af4c6ed2e2c6404aa27ca19c7f39ddb : update Linux kernel when convenient.

Data as of 26 Oct 2026, 13:47 UTC

Severity

Unrated

Rated by Threat Radar · CVSS not yet scored by NVD

EPSS: 0.2% chance of exploitation in 30 days – higher than 13% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in e935cd525af4c6ed2e2c6404aa27ca19c7f39ddb, dd1a334523ba533cba63caf593a7329d8e0e5e6e, d11a260bd7dfc6f6ccd43e1b930050f24e70cd5f +2

Exploitation evidence

Disclosed: evidence found.
CVE published 15 Aug 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade to a fixed release listed under Affected software.

Affected software

Product	Affected	Fixed in
LinuxLinux	Affected ≥ cfd68b33094e1a92249850ff3c3c92ae9112a541, < e935cd525af4c6ed2e2c6404aa27ca19c7f39ddb	Fixed in e935cd525af4c6ed2e2c6404aa27ca19c7f39ddb
LinuxLinux	Affected ≥ cfd68b33094e1a92249850ff3c3c92ae9112a541, < dd1a334523ba533cba63caf593a7329d8e0e5e6e	Fixed in dd1a334523ba533cba63caf593a7329d8e0e5e6e
LinuxLinux	Affected ≥ cfd68b33094e1a92249850ff3c3c92ae9112a541, < d11a260bd7dfc6f6ccd43e1b930050f24e70cd5f	Fixed in d11a260bd7dfc6f6ccd43e1b930050f24e70cd5f
LinuxLinux	Affected ≥ cfd68b33094e1a92249850ff3c3c92ae9112a541, < 82b62eda68abfb7a33ac40f24b8c4128c2891148	Fixed in 82b62eda68abfb7a33ac40f24b8c4128c2891148
LinuxLinux	Affected ≥ cfd68b33094e1a92249850ff3c3c92ae9112a541, < 59adeedebf02aa1c203de1d2b67ec45bfab7a3c6	Fixed in 59adeedebf02aa1c203de1d2b67ec45bfab7a3c6
LinuxLinux	Affected =5.18	Fixed in–

Description

In the Linux kernel, the following vulnerability has been resolved: s390/zcrypt: Close speculative mem read possibility The domain value is extracted from a given CCA or EP11 ioctl struct when a CPRB is about to be sent. Thus this is a user controlled value. Under some special conditions (custom device node used, administrative load) this value is used as an array index after bounds checking, but without speculation barrier. Add the missing array_index_nospec() call to prevent speculative execution where this domain value is used.

References

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