Vulnerability in Audiobookshelf (CVE-2026-42886)
Summary
Vulnerability in Audiobookshelf (CVE-2026-42886). Risk of unauthorized operations or information disclosure. Exploitable via POST /api/backups/upload. Mitigation: upgrade to 2.32.2 or later.
Original description
The description as published by the source.
Audiobookshelf is a self-hosted audiobook and podcast server. Prior to 2.32.2, the POST /api/backups/upload endpoint decompresses the details entry from an uploaded .audiobookshelf ZIP file entirely into memory using zip.entryData(), with no limit on the decompressed size. The upload middleware also has no file size limit. An admin user can upload a crafted ZIP containing a highly compressed details entry that, when decompressed, consumes hundreds of megabytes or gigabytes of memory, crashing the server process via out-of-memory. This vulnerability is fixed in 2.32.2.
Source: NIST National Vulnerability Database NVD GitHub Advisory
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 CVE-2026-42886 has been found in Audiobookshelf.
Attackers can target a specific entry point like POST /api/backups/upload over the network to misuse the product.
Risk of unauthorized operations or information disclosure. CVSS score: 4.9/10.
What to do: upgrade Audiobookshelf to 2.32.2 or later.
If unsure, ask your IT team or search "Audiobookshelf CVE-2026-42886" on the vendor's site.
CVE-2026-42886 (Audiobookshelf) — CWE-409 / CVSS v3 4.9
Attack vector: remote (network-reachable) / no user interaction
Attack surface: POST /api/backups/upload
Patched: 2.32.2 — 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.
A vulnerability (CWE-409) exists in Audiobookshelf. Attackers reach the vulnerable code path via POST /api/backups/upload.
Check the vendor advisory for the affected versions of Audiobookshelf. Attack surface: POST /api/backups/upload.
Severity: Medium (CVSS 4.9/10). Risk of unauthorized operations or information disclosure.
Update to 2.32.2.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual POST /api/backups/upload requests with malformed payloads or SQL meta-characters. Run grep -r 'Audiobookshelf' . 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
-
1Identify exposure identify
grep -r 'Audiobookshelf' . | 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
Audiobookshelfを grep し、稼働しているサービス・バージョンを把握する。 -
2Hunt for indicators of compromise detect
grep 'POST /api/backups/upload' /var/log/nginx/access.log | grep -E '(unusual_payload|sqli_pattern)'アクセスログで
POST /api/backups/uploadへの異常なリクエスト (不正な認証ヘッダ・SQLメタ文字)を過去 30〜90日分捜索。WAF/SIEM があれば該当パスのアラート発火履歴を確認。 -
3Apply patch patch
Upgrade Audiobookshelf to 2.32.2ステージング環境で 2.32.2 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と、Step 2 で見つけた異常検知の続報チェックを含めること。
-
4Post-deployment verification verify
Replay attack against POST /api/backups/upload on staging to confirm patch closes the vector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 Step 2 と同じログクエリでアラート再発が無いか継続監視。
References
- advisory github.com
- advisory github.com
- advisory nvd.nist.gov