CVE-2026-74466 json
s390/zcrypt: Close speculative mem read possibility
published 2026-08-15 2 mo ago modified 2026-10-30 10 d ago also EUVD-2026-59659
- cvss
- —
- not scored
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 8%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- Linux Linux 6.1.191, 6.6.160, 6.12.114, 6.18.57, 7.1.8, 7.2
- linux Debian 13 6.12.115-2
- linux Debian 14 7.1.8-1
debian advisories DEBIAN-CVE-2026-74466
- linux Ubuntu 26.04 LTS 7.0.0-42.42
- linux-aws Ubuntu 26.04 LTS 7.0.0-1016.17
- linux-gcp Ubuntu 26.04 LTS 7.0.0-1016.18
- linux-ibm Ubuntu 26.04 LTS 7.0.0-1017.17
- linux-riscv Ubuntu 26.04 LTS 7.0.0-42.42.1
- linux-oracle Ubuntu 26.04 LTS 7.0.0-1015.16
- linux-hwe-7.0 Ubuntu 24.04 LTS 7.0.0-42.42~24.04.1
- linux-oem-7.0 Ubuntu 26.04 LTS 7.0.0-1017.17
ubuntu advisories UBUNTU-CVE-2026-74466
Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0
- git.kernel.org/stable/c/55ac533c568a5dcaa41cd26d6e089f9dff2a7c22 commit
- git.kernel.org/stable/c/dd1a334523ba533cba63caf593a7329d8e0e5e6e commit
- git.kernel.org/stable/c/d11a260bd7dfc6f6ccd43e1b930050f24e70cd5f commit
- git.kernel.org/stable/c/59adeedebf02aa1c203de1d2b67ec45bfab7a3c6 commit
- git.kernel.org/stable/c/82b62eda68abfb7a33ac40f24b8c4128c2891148 commit
- git.kernel.org/stable/c/e935cd525af4c6ed2e2c6404aa27ca19c7f39ddb commit
Vendor advisories
What the vendors themselves say about their products: affected, fixed or not affected, and what to do.
red hat product security vex CVE-2026-74466 updated cvss 5.5
kernel: s390/zcrypt: Close speculative mem read possibility
-
Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +83 more Red Hat Enterprise Linux 10 kernelaffected: workaround, no fix available “Fix deferred”
-
Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 more Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +8 more Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-rt, kernel-core, kernel-tools, +29 morenot affected: vulnerable code not present
Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf
Exploit prediction
0.19% chance of exploitation in the next 30 days, higher than 8% of all scored CVEs (FIRST EPSS, 2026-11-08).
Affected products
- Linux Linux
Classification
- Technology feeds
References
- git.kernel.org /stable/c/55ac533c568a5dcaa41cd26d6e089f9dff2a7c22
- git.kernel.org /stable/c/dd1a334523ba533cba63caf593a7329d8e0e5e6e
- git.kernel.org /stable/c/d11a260bd7dfc6f6ccd43e1b930050f24e70cd5f
- git.kernel.org /stable/c/59adeedebf02aa1c203de1d2b67ec45bfab7a3c6
- git.kernel.org /stable/c/82b62eda68abfb7a33ac40f24b8c4128c2891148
- git.kernel.org /stable/c/e935cd525af4c6ed2e2c6404aa27ca19c7f39ddb
Sources
- CVE List CVE-2026-74466
- NVD CVE-2026-74466
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