Authentication Bypass in pterodactyl/panel (CVE-2021-41129)
Summary
Authentication bypass in pterodactyl/panel (CVE-2021-41129). Successful exploitation can lead to full system takeover. Exploitable via confirmation_token. Mitigation: upgrade to 1.6.2 or later.
Original description
The description as published by the source.
Pterodactyl is an open-source game server management panel built with PHP 7, React, and Go. A malicious user can modify the contents of a confirmation_token input during the two-factor authentication process to reference a cache value not associated with the login attempt. In rare cases this can allow a malicious actor to authenticate as a random user in the Panel. The malicious user must target an account with two-factor authentication enabled, and then must provide a correct two-factor authentication token before being authenticated as that user. Due to a validation flaw in the logic handling user authentication during the two-factor authentication process a malicious user can trick the system into loading credentials for an arbitrary user by modifying the token sent to the server. This authentication flaw is present in the LoginCheckpointController@__invoke method which handles two-factor authentication for a user. This controller looks for a request input parameter called confirmation_token which is expected to be a 64 character random alpha-numeric string that references a value within the Panel's cache containing a user_id value. This value is then used to fetch the user that attempted to login, and lookup their two-factor authentication token. Due to the design of this system, any element in the cache that contains only digits could be referenced by a malicious user, and whatever value is stored at that position would be used as the user_id. There are a few d…
Source: OSV.dev (Open Source Vulnerabilities) NVD GitHub Advisory 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 CVE-2021-41129 has been found in pterodactyl/panel.
Attackers can target a specific entry point like confirmation_token over the network to misuse the product.
Successful exploitation can lead to full system takeover.
What to do: upgrade pterodactyl/panel to 1.6.2 or later.
If unsure, ask your IT team or search "pterodactyl/panel CVE-2021-41129" on the vendor's site.
CVE-2021-41129 (pterodactyl/panel) — CWE-287
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Attack surface: confirmation_token / user_id
Patched: 1.6.2 — 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.
Authentication bypass (CWE-287) exists in pterodactyl/panel. Attackers reach the vulnerable code path via confirmation_token without authentication.
Check the vendor advisory for the affected versions of pterodactyl/panel. Attack surface: confirmation_token / user_id.
Severity: ?. Successful exploitation can lead to full system takeover.
Update to 1.6.2.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'pterodactyl/panel' . 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
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1Identify exposure identify
grep -r 'pterodactyl/panel' . | 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
pterodactyl/panelを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade pterodactyl/panel to 1.6.2ステージング環境で 1.6.2 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を含めること。
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3Post-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
References
- advisory github.com
- advisory nvd.nist.gov
- advisory github.com
- advisory github.com
- package github.com
- patch github.com