Path Traversal in contao/contao (CVE-2026-55825)
Summary
Path traversal in contao/contao (CVE-2026-55825). Risk of unauthorized operations or information disclosure. Exploitable via jobUuid. Mitigation: upgrade to 5.7.7 or later.
Original description
The description as published by the source.
Summary
An authenticated backend user who can access one job can request an attachment identifier containing ../ segments and make the job attachment download endpoint read a file from another job directory inside var/job-attachments.
The controller authorizes only the jobUuid route parameter. The later attachment lookup joins that authorized job UUID with the attacker-controlled identifier, then passes the combined path to the virtual filesystem. VirtualFilesystem::resolve() canonicalizes the whole path and only rejects paths that escape the filesystem mount, so authorized-job/../victim-job/debug_log.csv becomes victim-job/debug_log.csv.
This is a cross-job authorization bypass for known job attachment paths. It is not a practical brute-force against unknown jobs because job directories are UUID v4 values.
Root Cause
JobsController::downloadJobAttachment() checks access to the route jobUuid before loading the attachment:
$job = $this->jobs->getByUuid($jobUuid);
if (!$job || !$this->jobs->hasAccess($job)) {
throw $this->createNotFoundException();
}
$attachment = $this->jobs->getAttachment($jobUuid, $identifier);
Jobs::getAttachment() then resolves a path built from the authorized job UUID and the attacker-controlled identifier:
$fileItem = $this->jobAttachmentsStorage->get($this->getAttachmentIdentifier($job, $identifier));
return $job->getUuid().'/'.$identifier;
VirtualFilesystem::resolve() canonica…
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-2026-55825 has been found in contao/contao.
Attackers can target a specific entry point like jobUuid over the network to misuse the product.
Risk of unauthorized operations or information disclosure. CVSS score: 3.1/10.
What to do: upgrade contao/contao to 5.7.7 or later.
If unsure, ask your IT team or search "contao/contao CVE-2026-55825" on the vendor's site.
CVE-2026-55825 (contao/contao) — CWE-22 / CVSS v3 3.1
Attack vector: remote (network-reachable) / no user interaction
Attack surface: jobUuid / identifier / FilesystemItem / debug_log.csv
Patched: 5.7.7 — 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.
Path traversal (CWE-22) exists in contao/contao. Attackers reach the vulnerable code path via jobUuid.
Check the vendor advisory for the affected versions of contao/contao. Attack surface: jobUuid / identifier / FilesystemItem / debug_log.csv.
Severity: Low (CVSS 3.1/10). Risk of unauthorized operations or information disclosure.
Update to 5.7.7.
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 'contao/contao' . 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 'contao/contao' . | 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
contao/contao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 contao/contao to 5.7.7ステージング環境で 5.7.7 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。
-
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 nvd.nist.gov
- package github.com
- web github.com
- web contao.org
- web github.com
- web github.com
- web github.com