Vulnerability in libio-compress-perl (DEBIAN-CVE-2026-48959)

Summary

Vulnerability in libio-compress-perl (DEBIAN-CVE-2026-48959). Risk of unauthorized operations or information disclosure. Mitigation: upgrade to 2.220-1 or later.

Original description

The description as published by the source.

IO::Uncompress::Unzip versions before 2.220 for Perl allow CPU exhaustion via per-byte read loop in fastForward. fastForward() compares length $offset (the digit count of the offset, 1 to 19) against the chunk size $c instead of $offset itself, so $c shrinks from 16 KiB to 1-19 bytes per iteration. Extracting a named entry from an attacker supplied zip via IO::Uncompress::Unzip->new($zip, Name => $target) drives a per-byte read loop scaling with the entry's compressed size, up to the non-Zip64 4 GiB cap.

Source: OSV.dev (Open Source Vulnerabilities) OSV

Auto-generated summary

Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.

A vulnerability tracked as DEBIAN-CVE-2026-48959 has been found in libio-compress-perl.
Risk of unauthorized operations or information disclosure.
What to do: upgrade libio-compress-perl to 2.220-1 or later.
If unsure, ask your IT team or search "libio-compress-perl DEBIAN-CVE-2026-48959" on the vendor's site.

DEBIAN-CVE-2026-48959 (libio-compress-perl)
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Patched: 2.220-1 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.

❓ What is the problem

A vulnerability (unclassified) exists in libio-compress-perl.

📍 Affected scope

Check the vendor advisory for the affected versions of libio-compress-perl.

🔥 Severity

Severity: ?. Risk of unauthorized operations or information disclosure.

🔧 How to fix

Update to 2.220-1.

🛡️ Workaround

Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.

🔍 Detection

Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'libio-compress-perl' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.

Response actions

Concrete steps and command examples for SOC/SRE teams to execute in order

1
Identify exposure identify
```
grep -r 'libio-compress-perl' . | grep -v node_modules
```
リポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で libio-compress-perl を grep し、稼働しているサービス・バージョンを把握する。
2
Apply patch patch
```
Upgrade libio-compress-perl to 2.220-1
```
ステージング環境で 2.220-1 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
3
Post-deployment verification verify
```
Confirm patched version is live in production
```
パッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。

Affected packages

Debian:11 libio-compress-perl

[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]

Debian:12 libio-compress-perl

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.204-1+deb12u1"}]}]

Debian:13 libio-compress-perl

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.213-1+deb13u1"}]}]

Debian:14 libio-compress-perl

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.220-1"}]}]

Debian:11 perl

[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]

Debian:12 perl

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.36.0-7+deb12u4"}]}]

Debian:13 perl

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.40.1-6+deb13u1"}]}]

Debian:14 perl

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.40.1-8"}]}]

References

advisory security-tracker.debian.org