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TI-2026-39262 Aliases CVE-2026-54370GHSA-r45p-762r-6pqj

acl < 2.4.0 TOCTOU Symlink Traversal via getfacl/setfacl/chacl

Priority LOW 32CWE-367Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
High
Attack requirements
None
Impact type
—
Confidentiality · integrity · availability
High · High · None
Fix status
Partial Red Hat: 13 fixed, 4 without a fix

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

Summary

acl before version 2.4.0 contains a time-of-check to time-of-use (TOCTOU) race condition vulnerability that allows local attackers to escalate privileges by replacing a pathname component with a symbolic link between an lstat() check and subsequent symlink-following operations such as stat(), chown(), chmod(), acl_get_file(), and acl_set_file(). Attackers who control a pathname component can redirect file access control list operations to arbitrary files when getfacl, setfacl, or chacl is invoked by a privileged process over an attacker-controlled path, resulting in local privilege escalation.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00088 0th percentileScored 2026-11-07
Fix Partial acl (acl project): 2.4.0Red Hat: 24 advisoriesRed Hat: 13 fixed, 4 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

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

Affected products

VendorProductAffected versionsFixed inStatusSource
acl projectaclbefore 2.4.02.4.0Patch availableCNA
  • acl Vendoracl project Affected before 2.4.0 Fixed in 2.4.0 Patch available CNA

Remediation

  • Fix · CNA acl (acl project) Fixed in 2.4.0

Red Hat 24 advisories

  • RHSA-2026:82888 Released 2026-10-14 · Red Hat rating Important
    cert-manager Operator for Red Hat OpenShift 1.17.2
    • Cert Manager support for Red Hat OpenShift release 1.17 registry.redhat.io/cert-manager/cert-manager-operator-bundle
  • RHSA-2026:82857 Released 2026-10-14 · Red Hat rating Important
    cert-manager Operator for Red Hat OpenShift 1.18.2
    • Cert Manager support for Red Hat OpenShift release 1.18 registry.redhat.io/cert-manager/cert-manager-operator-bundle
  • RHSA-2026:82372 Released 2026-10-13 · Red Hat rating Important
    cert-manager Operator for Red Hat OpenShift 1.18.2
    • Cert Manager support for Red Hat OpenShift release 1.18 registry.redhat.io/cert-manager/cert-manager-operator-rhel9
Show 21 more Red Hat advisories
  • RHSA-2026:82354 Released 2026-10-13 · Red Hat rating Important
    cert-manager Operator for Red Hat OpenShift 1.18.2
    • Cert Manager support for Red Hat OpenShift release 1.18 registry.redhat.io/cert-manager/cert-manager-istio-csr-rhel9
  • RHSA-2026:82347 Released 2026-10-13 · Red Hat rating Important
    cert-manager Operator for Red Hat OpenShift 1.18.2
    • Cert Manager support for Red Hat OpenShift release 1.18 registry.redhat.io/cert-manager/jetstack-cert-manager-acmesolver-rhel9, registry.redhat.io/cert-manager/jetstack-cert-manager-rhel9
  • RHSA-2026:82336 Released 2026-10-13 · Red Hat rating Important
    cert-manager Operator for Red Hat OpenShift 1.17.1
    • Cert Manager support for Red Hat OpenShift release 1.17 registry.redhat.io/cert-manager/cert-manager-istio-csr-rhel9
  • RHSA-2026:82322 Released 2026-10-13 · Red Hat rating Important
    cert-manager Operator for Red Hat OpenShift 1.17.2
    • Cert Manager support for Red Hat OpenShift release 1.17 registry.redhat.io/cert-manager/cert-manager-operator-rhel9
  • RHSA-2026:82304 Released 2026-10-13 · Red Hat rating Important
    cert-manager Operator for Red Hat OpenShift 1.17.2
    • Cert Manager support for Red Hat OpenShift release 1.17 registry.redhat.io/cert-manager/jetstack-cert-manager-acmesolver-rhel9, registry.redhat.io/cert-manager/jetstack-cert-manager-rhel9
  • RHSA-2026:72502 Released 2026-09-28 · Red Hat rating Important
    cert-manager Operator for Red Hat OpenShift 1.20.1
    • Cert Manager support for Red Hat OpenShift release 1.20 registry.redhat.io/cert-manager/cert-manager-trust-manager-rhel9
  • RHSA-2026:72476 Released 2026-09-28 · Red Hat rating Important
    cert-manager Operator for Red Hat OpenShift 1.20.1
    • Cert Manager support for Red Hat OpenShift release 1.20 registry.redhat.io/cert-manager/cert-manager-operator-rhel9
  • RHSA-2026:72475 Released 2026-09-28 · Red Hat rating Important
    cert-manager Operator for Red Hat OpenShift 1.20.1
    • Cert Manager support for Red Hat OpenShift release 1.20 registry.redhat.io/cert-manager/cert-manager-istio-csr-rhel9
  • RHSA-2026:72470 Released 2026-09-28 · Red Hat rating Important
    cert-manager Operator for Red Hat OpenShift 1.20.1
    • Cert Manager support for Red Hat OpenShift release 1.20 registry.redhat.io/cert-manager/jetstack-cert-manager-acmesolver-rhel9, registry.redhat.io/cert-manager/jetstack-cert-manager-rhel9
  • RHSA-2026:72399 Released 2026-09-28 · Red Hat rating Important
    cert-manager Operator for Red Hat OpenShift 1.20.1
    • Cert Manager support for Red Hat OpenShift release 1.20 registry.redhat.io/cert-manager/cert-manager-operator-rhel9
  • RHSA-2026:72395 Released 2026-09-28 · Red Hat rating Important
    cert-manager Operator for Red Hat OpenShift 1.20.1
    • Cert Manager support for Red Hat OpenShift release 1.20 registry.redhat.io/cert-manager/cert-manager-istio-csr-rhel9
  • RHSA-2026:72394 Released 2026-09-28 · Red Hat rating Important
    cert-manager Operator for Red Hat OpenShift 1.20.1
    • Cert Manager support for Red Hat OpenShift release 1.20 registry.redhat.io/cert-manager/jetstack-cert-manager-rhel9
  • RHSA-2026:58981 Released 2026-08-24 · Red Hat rating Critical
    Red Hat Update Infrastructure 5.3 Technology Preview security update
    • Red Hat Update Infrastructure 5 registry.redhat.io/rhui5/cds-kubernetes-tp-rhel9, registry.redhat.io/rhui5/installer-tp-rhel9, registry.redhat.io/rhui5/rhua-tp-rhel9
  • RHSA-2026:53371 Released 2026-08-11 · Red Hat rating Important
    Insights proxy Container Image
    • Red Hat Insights proxy 1.5 registry.redhat.io/insights-proxy/insights-proxy-container-rhel9
  • RHSA-2026:50205 Released 2026-08-04 · Red Hat rating Important
    Red Hat build of OpenTelemetry 3.10.1 release
    • Red Hat OpenShift distributed tracing 3.10.1 registry.redhat.io/rhosdt/opentelemetry-collector-rhel9, registry.redhat.io/rhosdt/opentelemetry-rhel9-operator
  • RHSA-2026:46836 Released 2026-07-27 · Red Hat rating Important
    A Subscription Management tool for finding and reporting Red Hat product usage
    • Red Hat Discovery 2 registry.redhat.io/discovery/discovery-server-rhel9, registry.redhat.io/discovery/discovery-ui-rhel9
  • RHSA-2026:44481 Released 2026-07-23 · Red Hat rating Important
    Red Hat Update Infrastructure 5.2 security update
    • Red Hat Update Infrastructure 5 registry.redhat.io/rhui5/cds-kubernetes-rhel9, registry.redhat.io/rhui5/cds-rhel9, registry.redhat.io/rhui5/haproxy-rhel9 +2
  • RHSA-2026:43420 Released 2026-07-22 · Red Hat rating Important
    acl security update
    • Red Hat Enterprise Linux BaseOS (v. 8) acl-2.4.0-1.el8_10, libacl-2.4.0-1.el8_10, libacl-devel-2.4.0-1.el8_10
  • RHSA-2026:42736 Released 2026-07-21 · Red Hat rating Important
    acl security update
    • Red Hat Enterprise Linux AppStream (v. 9) libacl-devel-2.4.0-1.el9_8
    • Red Hat Enterprise Linux BaseOS (v. 9) acl-2.4.0-1.el9_8, libacl-2.4.0-1.el9_8
  • RHSA-2026:42739 Released 2026-07-21 · Red Hat rating Important
    acl security update
    • Red Hat Enterprise Linux AppStream (v. 10) libacl-devel-2.4.0-1.el10_2
    • Red Hat Enterprise Linux BaseOS (v. 10) acl-2.4.0-1.el10_2, libacl-2.4.0-1.el10_2
  • RHSA-2026:34351 Released 2026-07-01 · Red Hat rating Important
    Red Hat Hardened Images RPMs Security Update
    • Red Hat Hardened Images acl-2.4.0-0.1.hum1@aarch64, acl-2.4.0-0.1.hum1@src, acl-2.4.0-0.1.hum1@x86_64 +4

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    acl 2.4.0

    2 records Highest priority Priority LOW 2 LOW

    Other records, highest priority first

    • TI-2026-39261 acl < 2.4.0 Symlink Traversal Privilege Escalation via libacl FunctionsPriority LOW 37
    Show all 2 records →

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 6AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 7AffectedNo fix yet: Fix deferred
Red Hat OpenShift Container Platform 4AffectedNo fix yet: Fix deferred
Red Hat OpenShift Container Platform 5AffectedNo fix yet: Fix deferred
Cert Manager support for Red Hat OpenShift release 1.17Fixed RHSA-2026:82304, RHSA-2026:82322, RHSA-2026:82336, RHSA-2026:82888
Cert Manager support for Red Hat OpenShift release 1.18Fixed RHSA-2026:82347, RHSA-2026:82354, RHSA-2026:82372, RHSA-2026:82857
Cert Manager support for Red Hat OpenShift release 1.20Fixed RHSA-2026:72394, RHSA-2026:72395, RHSA-2026:72399, RHSA-2026:72470, RHSA-2026:72475, RHSA-2026:72476, RHSA-2026:72502
Red Hat Discovery 2Fixed RHSA-2026:46836
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2026:42739
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2026:42736
Red Hat Enterprise Linux BaseOS (v. 10)Fixed RHSA-2026:42739
Red Hat Enterprise Linux BaseOS (v. 8)Fixed RHSA-2026:43420
Red Hat Enterprise Linux BaseOS (v. 9)Fixed RHSA-2026:42736
Red Hat Hardened ImagesFixed RHSA-2026:34351
Red Hat Insights proxy 1.5Fixed RHSA-2026:53371
Red Hat OpenShift distributed tracing 3.10.1Fixed RHSA-2026:50205
Red Hat Update Infrastructure 5Fixed RHSA-2026:44481, RHSA-2026:58981
Not affected: 9 products
  • Cert Manager support for Red Hat OpenShift release 1.20
  • Red Hat Discovery 2
  • Red Hat Enterprise Linux AppStream (v. 10)
  • Red Hat Enterprise Linux AppStream (v. 9)
  • Red Hat Enterprise Linux BaseOS (v. 10)
  • Red Hat Enterprise Linux BaseOS (v. 8)
  • Red Hat Enterprise Linux BaseOS (v. 9)
  • Red Hat OpenShift distributed tracing 3.10.1
  • Red Hat Update Infrastructure 5

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-54370
  2. 2026-10-03 Alias added: GHSA-r45p-762r-6pqj
  3. 2026-10-14 Fix available: RHSA-2026:82304 · Red Hat
  4. 2026-10-14 Fix available: RHSA-2026:82322 · Red Hat
  5. 2026-10-14 Fix available: RHSA-2026:82336 · Red Hat
  6. 2026-10-14 Fix available: RHSA-2026:82372 · Red Hat
  7. 2026-10-14 Fix available: RHSA-2026:82354 · Red Hat
  8. 2026-10-14 Fix available: RHSA-2026:82347 · Red Hat
  9. 2026-10-15 Fix available: RHSA-2026:82857 · Red Hat
  10. 2026-10-15 Fix available: RHSA-2026:82888 · Red Hat
  11. 2026-10-16 Fix available: Cert Manager support for Red Hat OpenShift release 1.17, Cert Manager support for Red Hat OpenShift release 1.18 · Red Hat
  12. 2026-11-03 Fix available: Red Hat OpenShift distributed tracing 3.10.1 · Red Hat

References

Patch 1

Other 1

  • TI-2026-39261 acl < 2.4.0 Symlink Traversal Privilege Escalation via libacl Functions CVSS 4.0HIGH 8.4

Sources

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