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Fencer Intel
high 8.4

CVE-2026-57432 json

Perl versions before 5.40.5-RC1, from 5.41.0 before 5.42.3-RC1, from 5.43.0 before 5.43.11 have an integer overflow in S_measure_struct leading to an out-of-bounds heap read in pack and unpack

published 3mo ago modified yesterday also EUVD-2026-43502

cvss
8.4
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 11%
public exploits
0
none known

Summary

Perl versions before 5.40.5-RC1, from 5.41.0 before 5.42.3-RC1, from 5.43.0 before 5.43.11 have an integer overflow in S_measure_struct leading to an out-of-bounds heap read in pack and unpack.

S_measure_struct adds each item's size times its repeat count to a running total with no overflow check, so a large repeat count in a pack or unpack template wraps the signed SSize_t total negative. The @, X, and x position codes then guard their moves with a signed length comparison that passes when the length is negative, advancing the buffer pointer out of bounds.

A template derived from untrusted input can read heap memory past the buffer and return it to the caller.

Patch / fix

  • cpan perl 5.40.5-RC1, 5.42.3-RC1, 5.43.11
  • perl Debian 12 5.36.0-7+deb12u4
  • perl Debian 13 5.40.1-6+deb13u1
  • perl Debian 14 5.40.1-8

debian advisories DEBIAN-CVE-2026-57432

  • perl Ubuntu 22.04 LTS 5.34.0-3ubuntu1.8
  • perl Ubuntu 24.04 LTS 5.38.2-3.2ubuntu0.4
  • perl Ubuntu 26.04 LTS 5.40.1-7ubuntu0.3
  • perl Ubuntu Pro 14.04 LTS 5.18.2-2ubuntu1.7+esm8
  • perl Ubuntu Pro 16.04 LTS 5.22.1-9ubuntu0.9+esm3
  • perl Ubuntu Pro 18.04 LTS 5.26.1-6ubuntu0.7+esm3
  • perl Ubuntu Pro 20.04 LTS 5.30.0-9ubuntu0.5+esm3

ubuntu advisories UBUNTU-CVE-2026-57432

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

  • perl hummingbird 1 5.42.2-524.3.hum1
  • perl-B hummingbird 1 1.89-524.3.hum1
  • perl-if hummingbird 1 0.61.000-524.3.hum1
  • perl-IO hummingbird 1 1.55-524.3.hum1
  • perl-ph hummingbird 1 5.42.2-524.3.hum1
  • perl-lib hummingbird 1 0.65-524.3.hum1
  • perl-mro hummingbird 1 1.29-524.3.hum1
  • perl-Net hummingbird 1 1.04-524.3.hum1

red hat advisories RHSA-2026:39997

  • perl SLES for SAP 15 SP6, SLES for SAP 15 SP5, SLES for SAP 15 SP4 +13 more 5.26.1-150300.17.23.1
  • perl Linux Micro 6.1 5.38.2-slfo.1.1_3.1
  • perl Linux Micro 6.0 5.38.2-5.1
  • perl SLES 16.0, Linux Micro 6.2, SLES for SAP applications 16.0 5.42.0-160000.3.1
  • perl SLES LTSS Extended Security 12 SP5, SLES 12 SP5-LTSS 5.18.2-12.35.1

suse advisories SUSE-SU-2026:3558-1SUSE-SU-2026:3540-1SUSE-SU-2026:23075-1SUSE-SU-2026:23008-1SUSE-SU-2026:22847-1SUSE-SU-2026:22929-1

  • perl openSUSE Leap 16.0 5.42.0-160000.3.1

opensuse advisories openSUSE-SU-2026:21411-1

  • perl Alpine 3.24 5.42.3-r0

alpine advisories ALPINE-CVE-2026-57432

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • perl Azure Linux 3.0 5.38.2-514

azure linux advisories AZL-92297

Azure Linux vulnerability data, Copyright (c) Microsoft Corporation, from https://github.com/microsoft/AzureLinuxVulnerabilityData via OSV, under the MIT licence; changed: normalised to fixed package versions per release. MIT

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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-2026-57432 updated cvss 5.0

perl: Perl: Information disclosure via integer overflow in pack/unpack operations

  • Red Hat Enterprise Linux 6 perl, perl-CGI, perl-core, perl-CPAN, perl-libs, perl-parent, +39 more Red Hat Enterprise Linux 7 perl, perl-core, perl-CPAN, perl-libs, perl-tests, perl-macros, +11 more Red Hat Enterprise Linux 8 perl, perl-IO, perl-libs, perl-open, perl-Test, perl-Errno, +19 more Red Hat Enterprise Linux 9 perl, perl-B, perl-if, perl-IO, perl-ph, perl-lib, +92 more Red Hat Enterprise Linux 10 perl Red Hat OpenShift AI (RHOAI) rhoai/odh-workbench-codeserver-datascience-cpu-py312-rhel9
    +3 more products
    Red Hat OpenShift Container Platform 4 openshift/ose-rhel-coreos-8, openshift/ose-rhel-coreos-9 Red Hat OpenShift Container Platform 5 openshift/ose-rhel-coreos-9 Red Hat OpenShift Dev Spaces devspaces/code-rhel9
    affected: workaround, no fix available “Fix deferred”
  • Red Hat Hardened Images perl 5.42.2-524.3.hum1, perl-B 1.89-524.3.hum1, perl-IO 1.55-524.3.hum1, perl-Tie 4.6-524.3.hum1, perl-lib 0.65-524.3.hum1, perl-mro 1.29-524.3.hum1, +93 more
    fixed: vendor fix RHSA-2026:39997

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

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
total
Assessed
3mo ago

Exploit prediction

0.21% chance of exploitation in the next 30 days, higher than 11% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by version score vector
CISA ADP 3.1 8.4 CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD 3.1 8.4 CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CNA 3.1 8.4 CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

  • cpan perl
  • Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)
  • Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0)
  • Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0)
  • Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0)
  • Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0)

Classification

Weakness

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.