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TI-2026-40751 Aliases CVE-2026-56391GHSA-7xvj-m9x7-qgxq

Out‑of‑bounds Read in GNU coreutils

Priority LOW 20CWE-125Published · Updated

Key facts

Attack vector
Local
Privileges required
None
User interaction
Active
Attack complexity
Low
Attack requirements
None
Impact type
—
Confidentiality · integrity · availability
Low · None · Low
Fix status
Partial Red Hat: 2 fixed, 7 without a fix

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat.

Summary

GNU coreutils uniq is vulnerable to an out‑of‑bounds read due to incorrect handling of multibyte input when the -w (--check-chars) option is used. The find_field() function miscalculates the byte length of characters by repeatedly processing a fixed pointer instead of advancing through the input, resulting in an inflated length value. This incorrect length is later used in a memcmp operation, causing reads beyond the allocated buffer when processing crafted multibyte input. When running GNU coreutils uniq with attacker-provided arguments, this behavior leads to a crash and potential adjacent heap memory exposure. This issue has been fixed in the commit d64e35a8a4c0e4608321433e0d84d917e4e36371.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00131 2nd percentileScored 2026-11-07
Fix Partial Red Hat: 2 advisoriesRed Hat: 2 fixed, 7 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
GNUcoreutils9.5 – 9.11—No fix listedCNA
  • coreutils VendorGNU Affected 9.5 – 9.11 Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:gnu:coreutils:*:*:*:*:*:*:*:*9.5 – 9.11VulnerableGNU
  • cpe:2.3:a:gnu:coreutils:*:*:*:*:*:*:*:* Versions 9.5 – 9.11 Vulnerable ·GNU

Remediation

Red Hat 2 advisories

  • RHSA-2026:67886 Released 2026-09-16 · Red Hat rating Moderate
    coreutils security update
    • Red Hat Enterprise Linux BaseOS (v. 10) coreutils-9.5-8.el10_2.1, coreutils-single-9.5-8.el10_2.1
  • RHSA-2026:46515 Released 2026-07-27 · Red Hat rating Moderate
    Red Hat Hardened Images RPMs Security Update
    • Red Hat Hardened Images coreutils-9.11-5.1.hum1@aarch64, coreutils-9.11-5.1.hum1@src, coreutils-9.11-5.1.hum1@x86_64 +4

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 7AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 8AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 9AffectedNo fix yet: Fix deferred
Red Hat OpenShift AI (RHOAI)Affected—
Red Hat OpenShift Container Platform 4AffectedNo fix yet: Fix deferred
Red Hat OpenShift Container Platform 5AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux BaseOS (v. 10)Fixed RHSA-2026:67886
Red Hat Hardened ImagesFixed RHSA-2026:46515
Not affected: 2 products
  • Red Hat Enterprise Linux BaseOS (v. 10)
  • Red Hat OpenShift AI (RHOAI)

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-56391
  2. 2026-10-03 Alias added: GHSA-7xvj-m9x7-qgxq
  3. 2026-11-06 Affected versions changed · Red Hat
  4. 2026-11-06 Affected versions changed · Red Hat

References

Patch 1

Advisory 1

Other 1

  • TI-2017-13227 In GNU Coreutils through 8.29, chown-core.c in chown and chgrp does not prevent… CVSS 3.1HIGH 7.1
  • TI-2015-01675 fts.c in coreutils 8.4 allows local users to delete arbitrary files. CVSS 3.1MEDIUM 5.1
  • TI-2015-03409 Integer overflow in the keycompare_mb function in sort.c in sort in GNU Coreutils through… CVSS 3.1CRITICAL 9.8
  • TI-2014-07697 The parse_datetime function in GNU coreutils allows remote attackers to cause a denial of… CVSS 2.0HIGH 7.5
  • TI-2015-03408 The keycompare_mb function in sort.c in sort in GNU Coreutils through 8.23 on 64-bit… CVSS 3.1HIGH 7.8
  • TI-2024-00631 Coreutils: heap overflow in split --line-bytes with very long lines CVSS 3.1MEDIUM 5.5
See all 11 →

Sources

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