high 7.5

CVE-2026-9538 json

Archive::Tar versions before 3.10 for Perl allow memory exhaustion via attacker controlled entry size field in tar header

published 2026-05-26 5 mo ago modified 2026-07-23 3 mo ago also EUVD-2026-31775

cvss: 7.5; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.5%; EPSS 0.5% chance of exploitation in 30 days, percentile 44%
public exploits: 0; none known

Archive::Tar versions before 3.10 for Perl allow memory exhaustion via attacker controlled entry size field in tar header.

_read_tar() reads each entry's payload with $handle->read($$data, $block), where $block is derived from the entry's 12-byte size field in the tar header with no upper bound on that value.

A crafted header declaring a multi-gigabyte size causes Perl to allocate a scalar of that size.

Patch / fix

fixed in 1 distros 6 links 1

BINGOS Archive::Tar 3.10

debian ubuntu red hat almalinux rocky linux alpine

perl Debian 14 5.42.3-1

debian advisories DEBIAN-CVE-2026-9538

perl Ubuntu 24.04 LTS 5.38.2-3.2ubuntu0.4

ubuntu advisories UBUNTU-CVE-2026-9538

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-Archive-Tar RHEL 9 2.38-6.el9_8.2
perl-Archive-Tar RHEL 10.2 3.02-512.el10_2.2
perl-Archive-Tar RHEL 8 2.30-3.el8_10
perl RHEL 8 4:5.32.1-474.module+el8.10.0+24099+8aa2f756
perl-B RHEL 8 1.80-474.module+el8.10.0+24099+8aa2f756
perl-if RHEL 8 0.60.800-474.module+el8.10.0+24099+8aa2f756
perl-IO RHEL 8 1.43-474.module+el8.10.0+24099+8aa2f756
perl-ph RHEL 8 5.32.1-474.module+el8.10.0+24099+8aa2f756

red hat advisories RHSA-2026:49525 RHSA-2026:49523 RHSA-2026:49524 RHSA-2026:48225

perl-Archive-Tar AlmaLinux 10 3.02-512.el10_2.2
perl-Archive-Tar AlmaLinux 8 2.30-3.el8_10
perl-Archive-Tar AlmaLinux 9 2.38-6.el9_8.2
perl AlmaLinux 8 4:5.32.1-474.module_el8.10.0+4162+0aac7c4c
perl AlmaLinux 8 4:5.32.1-474.module_el8.10.0+4240+a58b978c
perl-B AlmaLinux 8 1.80-474.module_el8.10.0+4240+a58b978c
perl-B AlmaLinux 8 1.80-474.module_el8.10.0+4162+0aac7c4c
perl-if AlmaLinux 8 0.60.800-474.module_el8.10.0+4162+0aac7c4c

almalinux advisories ALSA-2026:49523 ALSA-2026:49524 ALSA-2026:49525 ALSA-2026:48225

perl-Archive-Tar Rocky Linux 10 3.02-512.el10_2.2
perl-Archive-Tar Rocky Linux 9 2.38-6.el9_8.2
perl-Archive-Tar Rocky Linux 8 2.30-3.el8_10
perl Rocky Linux 8 4:5.32.1-474.module+el8.10.0+40155+64ce2d41
perl-Env Rocky Linux 8 1.04-396.module+el8.10.0+1616+0d20cc68
perl-Env Rocky Linux 8 1.04-396.module+el8.10.0+40155+64ce2d41
perl-Env Rocky Linux 8 1.04-396.module+el8.6.0+878+f93dfff7
perl-Env Rocky Linux 8 1.04-396.module+el8.6.0+882+2fa1e48f

rocky linux advisories RLSA-2026:49523 RLSA-2026:49525 RLSA-2026:49524 RLSA-2026:48225

perl Alpine 3.24 5.42.3-r0

alpine advisories ALPINE-CVE-2026-9538

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

github.com/jib/archive-tar-new@f9af014 commit

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-2026-9538 updated 2026-11-05 cvss 7.5

perl-Archive-Tar: perl-Archive-Tar: Denial of Service via crafted tar header with large entry size

Red Hat Enterprise Linux 7 perl-Archive-Tar
affected: workaround, no fix available
Red Hat Enterprise Linux AppStream (v. 8) perl 5.32.1-474.module+el8.10.0+24099+8aa2f756, perl-B 1.80-474.module+el8.10.0+24099+8aa2f756, perl-URI 1.76-5.module+el8.10.0+21354+3ad137bb, perl-CPAN 2.28-5.module+el8.10.0+21354+3ad137bb, perl-IO 1.43-474.module+el8.10.0+24099+8aa2f756, perl-Tie 4.6-474.module+el8.10.0+24099+8aa2f756, +213 more
fixed: vendor fix RHSA-2026:48225
Red Hat Enterprise Linux AppStream (v. 9) perl-Archive-Tar 2.38-6.el9_8.2
fixed: vendor fix RHSA-2026:49525
Red Hat Enterprise Linux AppStream (v. 10) perl-Archive-Tar 3.02-512.el10_2.2
fixed: vendor fix RHSA-2026:49523
Red Hat Enterprise Linux BaseOS (v. 8) perl-Archive-Tar 2.30-3.el8_10
fixed: vendor fix RHSA-2026:49524

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: yes
Technical impact: partial
Assessed: 5 mo ago (2026-05-28)

Exploit prediction

0.52% chance of exploitation in the next 30 days, higher than 44% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CISA ADP	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
NVD	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CNA	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Affected products

BINGOS Archive::Tar

Classification

Weakness

CWE-789 Memory Allocation with Excessive Size Value

References

github.com /jib/archive-tar-new/commit/f9af01426038e29d9578825a0cd3626946ab08c7.patch
patch
metacpan.org /release/BINGOS/Archive-Tar-3.10/changes
release-notes
openwall.com /lists/oss-security/2026/05/26/4
mailing-list, third-party-advisory

Sources

CVE List CVE-2026-9538
NVD CVE-2026-9538

Fencer Vulns 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.

Summary