Vulnerability in streamlink (UBUNTU-CVE-2026-44353)

Summary

Vulnerability in streamlink (UBUNTU-CVE-2026-44353). Confidential information can be exposed externally. Mitigation: upgrade to 8.4.0 or later.

Original description

The description as published by the source.

Streamlink is a CLI utility which pipes video streams from various services into a video player. Prior to 8.4.0, Streamlink's HLS and DASH parsers do not validate the URI scheme of segment entries and other resources. A remote .m3u8 HLS playlist or .mpd DASH manifest can list file:///path/to/file as a segment, and streamlink will read that local file and write its contents to the output stream. This vulnerability is fixed in 8.4.0.

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 UBUNTU-CVE-2026-44353 has been found in streamlink.
Confidential information can be exposed externally.
What to do: upgrade streamlink to 8.4.0 or later.
If unsure, ask your IT team or search "streamlink UBUNTU-CVE-2026-44353" on the vendor's site.

UBUNTU-CVE-2026-44353 (streamlink)
Attack vector: remote (network-reachable) / unauthenticated
Patched: 8.4.0 — 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 streamlink.

📍 Affected scope

Check the vendor advisory for the affected versions of streamlink.

🔥 Severity

Severity: ?. Confidential information can be exposed externally.

🔧 How to fix

Update to 8.4.0.

🛡️ 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 'streamlink' . 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 'streamlink' . | 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 streamlink 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 streamlink to 8.4.0
```
ステージング環境で 8.4.0 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。