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TI-2026-81843 Aliases CVE-2026-99136GHSA-mgww-4g2j-r877

Race condition in Linux dm-crypt reports failed I/O as successful

Priority LOW 30Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
High
Impact type
—
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 7 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat.

Summary

The dm-crypt device mapper target in the Linux kernel is affected in versions from 2.6.28.9 before 2.6.29 and from 2.6.29 onward. A race condition in crypt_dec_pending reads the I/O error status before dropping the last reference, so another context can set the error in between and the bio completes with a stale status. A local attacker with low privileges can cause a failed read, or a read that was never decrypted, to be reported as successful, and a failed write to be reported as successful too.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

Description from the CNA

In the Linux kernel, the following vulnerability has been resolved: dm-crypt: fix a tiny race condition in crypt_dec_pending crypt_dec_pending reads io->error before calling atomic_dec_and_test. Another context, for example crypt_endio called from an interrupt, may set io->error and drop its reference between the read and the decrement. crypt_dec_pending then drops the last reference and completes the bio with the stale status - so a read that failed and was never decrypted, or a write that failed, is reported as successful. The read was placed before the decrement by commit b35f8caa0890 ("dm crypt: wait for endio to complete before destruction"), because that commit freed dm_crypt_io before calling bio_endio. This is no longer the case, dm_crypt_io lives in the per-bio data now. Read io->error after atomic_dec_and_test instead. atomic_dec_and_test is fully ordered, so no additional barrier is needed.

Why it matters now

EPSS 0.00122 2nd percentileScored 2026-11-07
Fix Partial Linux (Linux): 2.6.29, 5.10.273, 5.15.224 +6Red Hat: 7 without a fix

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux2.6.28.9 to before 2.6.292.6.29Patch availableCNA
LinuxLinux2.6.29 and later5.10.273, 5.15.224, 6.1.191, 6.6.161, 6.12.115, 6.18.59, 7.2.13, 7.3Patch availableCNA
  • Linux VendorLinux Affected 2.6.28.9 to before 2.6.29 Fixed in 2.6.29 Patch available CNA
  • Linux VendorLinux Affected 2.6.29 and later Fixed in 5.10.273, 5.15.224, 6.1.191, 6.6.161, 6.12.115, 6.18.59, 7.2.13, 7.3 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*——Linux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions — — ·Linux

Remediation

Linux kernel fixed versions are 2.6.29, 5.10.273, 5.15.224, 6.1.191, 6.6.161, 6.12.115, 6.18.59, 7.2.13 and 7.3. Red Hat lists no fix planned for Red Hat Enterprise Linux 6 and no fix available for Red Hat Enterprise Linux 7, 8, 9 and 10 and OpenShift Container Platform 4 and 5.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

  • Fix · CNA Linux (Linux) Fixed in 2.6.29
  • Fix · CNA Linux (Linux) Fixed in 5.10.273, 5.15.224, 6.1.191, 6.6.161, 6.12.115, 6.18.59, 7.2.13, 7.3

Vendor assessments

Red Hat

Red Hat rating: Low. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 10AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 7AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 8AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 9AffectedNo fix yet: Fix deferred
Red Hat OpenShift Container Platform 4AffectedNo fix yet: Fix deferred
Red Hat OpenShift Container Platform 5AffectedNo fix yet: Fix deferred

Timeline

  1. 2026-10-28 Threatist record created from CVE-2026-99136
  2. 2026-10-28 Alias added: GHSA-mgww-4g2j-r877
  3. 2026-10-30 Affected versions changed · Red Hat
  4. 2026-10-30 CVSS score added · Red Hat
  5. 2026-10-30 Affected versions changed · Red Hat
  6. 2026-10-30 Fix available: Linux/Linux@056bf8322e39a48026df352d6227ec03dd8cd032, Linux/Linux@445a6883f46d3ab1ff545199a8cc1d5834936d3f, Linux/[email protected] +7 · CNA
  7. 2026-10-30 5 new references · CNA
  8. 2026-10-31 CVSS score added · CNA

References

Other 8

  • TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
  • TI-2021-02452 Incorrect authorization in Ubuntu linux kernel KEVCVSS 3.1HIGH 8.8
  • TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
  • TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
  • TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
See all 21741 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences