Vulnerability in github.com/knadh/listmonk (CVE-2026-34828)
Summary
Vulnerability in github.com/knadh/listmonk (CVE-2026-34828). Confidential information can be exposed externally. Exploitable via GET /api/profile. Mitigation: upgrade to 1.1.1-0.20260329113754-1b5e8d38c778 or later.
Original description
The description as published by the source.
listmonk is a standalone, self-hosted, newsletter and mailing list manager. From version 4.1.0 to before version 6.1.0, a session management vulnerability allows previously issued authenticated sessions to remain valid after sensitive account security changes, specifically password reset and password change. As a result, an attacker who has already obtained a valid session cookie can retain access to the account even after the victim changes or resets their password. This weakens account recovery and session security guarantees. This issue has been patched in version 6.1.0.
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-2026-34828 has been found in github.com/knadh/listmonk.
Attackers can target a specific entry point like GET /api/profile over the network to misuse the product.
Confidential information can be exposed externally. CVSS score: 7.1/10.
What to do: upgrade github.com/knadh/listmonk to 1.1.1-0.20260329113754-1b5e8d38c778 or later.
If unsure, ask your IT team or search "github.com/knadh/listmonk CVE-2026-34828" on the vendor's site.
CVE-2026-34828 (github.com/knadh/listmonk) — CWE-613 / CVSS v3 7.1
Attack vector: remote (network-reachable) / no user interaction
Attack surface: GET /api/profile / PUT /api/profile
Patched: 1.1.1-0.20260329113754-1b5e8d38c778 — 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-613) exists in github.com/knadh/listmonk. Attackers reach the vulnerable code path via GET /api/profile.
Check the vendor advisory for the affected versions of github.com/knadh/listmonk. Attack surface: GET /api/profile / PUT /api/profile.
Severity: High (CVSS 7.1/10). Confidential information can be exposed externally.
Update to 1.1.1-0.20260329113754-1b5e8d38c778.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual GET /api/profile requests with malformed payloads or SQL meta-characters. Run grep -r 'github.com/knadh/listmonk' . 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 'github.com/knadh/listmonk' . | 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
github.com/knadh/listmonk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 'GET /api/profile' /var/log/nginx/access.log | grep -E '(unusual_payload|sqli_pattern)'アクセスログで
GET /api/profile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 github.com/knadh/listmonk to 1.1.1-0.20260329113754-1b5e8d38c778ステージング環境で 1.1.1-0.20260329113754-1b5e8d38c778 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 GET /api/profile 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。
Affected packages
References
- advisory github.com
- advisory nvd.nist.gov
- advisory github.com
- package github.com
- patch github.com
- web github.com