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TI-2026-11225 Aliases CVE-2026-13221GHSA-whhx-pv66-xhgq

Integer overflow in perl

Priority MEDIUM 46CWE-190Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · High · High
Fix status
Partial Red Hat: 8 fixed, 6 without a fix

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

Summary

Perl versions before 5.40.5-RC1, from 5.41.0 before 5.42.3-RC1, from 5.43.0 before 5.43.10 produce silently incorrect regular expression matches when an alternation of more than 65535 fixed string branches is compiled into a trie in Perl_study_chunk. When such branches are combined into a trie, the delta between the first branch and the shared tail is stored in a 16-bit field. A branch count above 65535 overflows the field, and the trie's match decision table is truncated with no warning or error. A pattern of this shape produces false positive matches (matching strings it should not) and false negative matches (failing to match strings it should). When such a pattern gates an access or filtering decision, the result is wrong.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00494 42nd percentileScored 2026-11-07
Fix Partial perl: 5.40.5-RC1, 5.42.3-RC1, 5.43.10Red Hat: 8 advisoriesRed Hat: 8 fixed, 6 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
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
—perlbefore 5.40.5-RC1; 5.41.0 to before 5.42.3-RC1; 5.43.0 to before 5.43.105.40.5-RC1, 5.42.3-RC1, 5.43.10Patch availableCNA
  • perl Vendor— Affected before 5.40.5-RC1; 5.41.0 to before 5.42.3-RC1; 5.43.0 to before 5.43.10 Fixed in 5.40.5-RC1, 5.42.3-RC1, 5.43.10 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:perl:perl:*:*:*:*:*:*:*:*up to 5.43.9VulnerablePerl
  • cpe:2.3:a:perl:perl:*:*:*:*:*:*:*:* Versions up to 5.43.9 Vulnerable ·Perl

Remediation

  • Fix · CNA perl Fixed in 5.40.5-RC1, 5.42.3-RC1, 5.43.10

Red Hat 8 advisories

  • RHSA-2026:79357 Released 2026-10-08 · Red Hat rating Important
    Red Hat Cost Management On-Premise container image update
    • Red Hat Cost Management On-Premise 1 registry.redhat.io/costmanagement/costmanagement-ui-rhel10
  • RHSA-2026:71446 Released 2026-09-29 · Red Hat rating Important
    OpenShift Container Platform 4.22.16 bug fix and security update
    • Red Hat OpenShift Container Platform 4.22 rhcos-aarch64-4.22.9.8.202609221802-0, rhcos-ppc64le-4.22.9.8.202609221802-0, rhcos-s390x-4.22.9.8.202609221802-0 +1
  • RHSA-2026:67956 Released 2026-09-16 · Red Hat rating Important
    Red Hat Update Infrastructure 5.3 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
Show 5 more Red Hat advisories
  • RHSA-2026:67278 Released 2026-09-14 · Red Hat rating Moderate
    perl:5.32 security update
    • Red Hat Enterprise Linux AppStream (v. 8) perl-4:5.32.1-475.module+el8.10.0+24767+f69b15b5.aarch64::perl:5.32, perl-4:5.32.1-475.module+el8.10.0+24767+f69b15b5.ppc64le::perl:5.32, perl-4:5.32.1-475.module+el8.10.0+24767+f69b15b5.s390x::perl:5.32 +47
  • RHSA-2026:67155 Released 2026-09-14 · Red Hat rating Moderate
    perl security update
    • Red Hat Enterprise Linux AppStream (v. 9) perl-4:5.32.1-484.el9_8, perl-Attribute-Handlers-1.01-484.el9_8, perl-AutoLoader-5.74-484.el9_8 +47
  • RHSA-2026:67156 Released 2026-09-14 · Red Hat rating Moderate
    perl security update
    • Red Hat Enterprise Linux AppStream (v. 10) perl-4:5.40.2-515.el10_2, perl-Attribute-Handlers-1.03-515.el10_2, perl-AutoLoader-5.74-515.el10_2 +47
  • RHSA-2026:67162 Released 2026-09-14 · Red Hat rating Moderate
    perl security update
    • Red Hat Enterprise Linux AppStream (v. 8) perl-4:5.26.3-423.el8_10.1, perl-Attribute-Handlers-0.99-423.el8_10.1, perl-Devel-Peek-1.26-423.el8_10.1 +16
    • Red Hat Enterprise Linux BaseOS (v. 8) perl-4:5.26.3-423.el8_10.1, perl-Errno-1.28-423.el8_10.1, perl-IO-1.38-423.el8_10.1 +5
  • RHSA-2026:39997 Released 2026-07-15 · Red Hat rating Moderate
    Red Hat Hardened Images RPMs Security Update
    • Red Hat Hardened Images perl-4:5.42.2-524.3.hum1@aarch64, perl-4:5.42.2-524.3.hum1@src, perl-4:5.42.2-524.3.hum1@x86_64 +47

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
Red Hat Enterprise Linux 7AffectedNo fix yet
Red Hat OpenShift AI (RHOAI)AffectedNo fix yet
Red Hat OpenShift Container Platform 4AffectedNo fix yet
Red Hat OpenShift Container Platform 5AffectedNo fix yet
Red Hat OpenShift Dev SpacesAffectedNo fix yet
Red Hat Cost Management On-Premise 1Fixed RHSA-2026:79357
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2026:67156
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2026:67162, RHSA-2026:67278
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2026:67155
Red Hat Enterprise Linux BaseOS (v. 8)Fixed RHSA-2026:67162
Red Hat Hardened ImagesFixed RHSA-2026:39997
Red Hat OpenShift Container Platform 4.22Fixed RHSA-2026:71446
Red Hat Update Infrastructure 5Fixed RHSA-2026:67956
Not affected: 1 product
  • Red Hat Update Infrastructure 5

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-13221
  2. 2026-10-03 Alias added: GHSA-whhx-pv66-xhgq
  3. 2026-10-09 Fix available: RHSA-2026:79357 · Red Hat
  4. 2026-10-09 Fix available: Red Hat Cost Management On-Premise 1 · Red Hat
  5. 2026-10-16 Affected versions changed · Red Hat
  6. 2026-10-30 Affected versions changed · Red Hat

References

Patch 2

Other 1

  • TI-2022-24100 In Perl 5.34.0, function S_find_uninit_var in sv.c has a stack-based crash that can lead… CVSS 3.1CRITICAL 9.8
  • TI-2012-05140 The _compile function in Maketext.pm in the Locale::Maketext implementation in Perl… CVSS 2.0HIGH 7.5
  • TI-2018-12932 Perl before 5.26.3 and 5.28.0 before 5.28.1 has a buffer overflow via a crafted regular… CVSS 3.0CRITICAL 9.8
  • TI-2018-12931 Perl before 5.26.3 and 5.28.x before 5.28.1 has a buffer overflow via a crafted regular… CVSS 3.0CRITICAL 9.8
  • TI-2018-05049 Heap-based buffer overflow in the pack function in Perl before 5.26.2 allows… CVSS 3.0CRITICAL 9.8
  • TI-2017-09493 Stack-based buffer overflow in the CPerlHost::Add method in win32/perlhost.h in Perl… CVSS 3.0CRITICAL 9.8
See all 45 →

Sources

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