CVE-2026-48959: IO::Uncompress::Unzip versions before 2.220 for Perl allow CPU exhaustion via per-byte read loop in fastForward

Published May 27, 2026
·
Updated

IO::Uncompress::Unzip versions before 2.220 for Perl allow CPU exhaustion via per-byte read loop in fastForward

Affected Software

5 affected componentsFixes available
cpan/IO-Compress/IO-Uncompress-Unzip<2.220
Microsoft azl3 perl 5.38.2-509
IBM AIX<=7.2
IBM AIX<=7.3
IBM PowerVM VIOS<=4.1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade Perl IO::Uncompress::Unzip to a version that resolves this vulnerability.

    Fixed in 2.220
  2. Compensating control

    As a mitigation until patched, avoid extracting attacker-supplied ZIP entries using IO::Uncompress::Unzip->new($zip, Name => $target) / IO::Uncompress::Unzip->new($zip, Name => $target), since extraction of a named entry drives a per-byte read loop scaling with the entry's compressed size (up to the non-Zip64 4 GiB cap).

Event History

May 27, 2026
CVE Published
via MITRE·02:29 AM
Data Sourced
via MITRE·02:29 AM
RemedyDescriptionWeakness
Data Sourced
via NVD·04:16 AM
DescriptionSeverityWeakness
Jun 2, 2026
Data Sourced
via Microsoft·08:01 AM
DescriptionSeverityWeaknessAffected Software
Updated
via Microsoft·08:01 AM
DescriptionSeverity
Aug 15, 2026
Data Sourced
via IBM·12:00 AM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is the severity of CVE-2026-48959?

CVE-2026-48959 is rated with a risk score of 30.

2

How do I fix CVE-2026-48959?

To fix CVE-2026-48959, upgrade to IO-Compress version 2.220 or later.

3

What versions are affected by CVE-2026-48959?

CVE-2026-48959 affects all versions of IO::Uncompress::Unzip for Perl before 2.220.

4

What kind of vulnerability is CVE-2026-48959?

CVE-2026-48959 is a vulnerability that allows CPU exhaustion due to a poor implementation in the fastForward function.

5

Who is impacted by CVE-2026-48959?

Users of IO::Uncompress::Unzip versions prior to 2.220 for Perl are impacted by CVE-2026-48959.

Contact

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