Bug 2496665

Summary: CVE-2026-9538 perl-Archive-Tar: perl-Archive-Tar: Denial of Service via crafted tar header with large entry size [fedora-all]
Product: [Fedora] Fedora Reporter: trgreene
Component: perl-Archive-TarAssignee: Jitka Plesnikova <jplesnik>
Status: CLOSED ERRATA QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: high Docs Contact:
Priority: high    
Version: rawhideCC: jplesnik, mspacek, perl-devel, rhughes, rstrode, steve
Target Milestone: ---Keywords: Security, SecurityTracking
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["b5c00ee7-f34c-4172-8223-ac36d0fdb32a"]}
Fixed In Version: perl-Archive-Tar-3.12-1.fc45 perl-Archive-Tar-3.12-1.fc44 perl-Archive-Tar-3.12-1.fc43 Doc Type: ---
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2026-08-15 01:15:30 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On:    
Bug Blocks: 2481315    

Description trgreene 2026-07-02 20:29:00 UTC 
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.

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.
Comment 1 Fedora Update System 2026-07-30 05:32:04 UTC 
FEDORA-2026-030f3f2029 (perl-Archive-Tar-3.12-1.fc43) has been submitted as an update to Fedora 43.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-030f3f2029
Comment 2 Fedora Update System 2026-07-31 01:44:14 UTC 
FEDORA-2026-030f3f2029 has been pushed to the Fedora 43 testing repository.
Soon you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --refresh --advisory=FEDORA-2026-030f3f2029`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-030f3f2029

See also https://fedoraproject.org/wiki/QA:Updates_Testing for more information on how to test updates.
Comment 3 Fedora Update System 2026-08-15 01:15:30 UTC 
FEDORA-2026-030f3f2029 (perl-Archive-Tar-3.12-1.fc43) has been pushed to the Fedora 43 stable repository.
If problem still persists, please make note of it in this bug report.