Path Traversal in egroupware/egroupware (CVE-2026-27823)
Summary
Path traversal in egroupware/egroupware (CVE-2026-27823). Risk of unauthorized operations or information disclosure. Exploitable via participant_role. Mitigation: upgrade to 23.1.20260224 or later.
Original description
The description as published by the source.
Summary
A critical vulnerability has been identified in EGroupware that may lead to Remote Code Execution (RCE).
The issue allows an authenticated attacker to execute arbitrary commands on the server. If user self-registration is enabled, the vulnerability may be exploitable without prior authentication.
The vulnerability stems from improper authorization checks combined with a file write primitive and an arbitrary file read vulnerability, which together enable full system compromise.
Details
1. Improper Authorization in SmallPartMediaRecorder::ajax_upload()
The vulnerability originates in:
EGroupware\SmallParT\Widgets\SmallPartMediaRecorder::ajax_upload()
The function attempts to verify whether the current user is a teacher of the specified course ID before allowing a file upload.
The critical authorization check ensures that the course access control list (ACL) contains:
$required_acl (self::ROLE_TEACHER, i.e., 3)
However, the course_acl value is derived from user-controlled request data.
Bypass Technique
A crafted request can manipulate the participant_role value inside the request body:
{
"video": {
"course_id": {
"participants": [
{
"account_id": "7",
"name": "Test",
"joined_at": "2026-01-10",
"participant_role": 3
}
],
"account_id": "7",
"course_id": "1"
},
"video_hash": ".",
"video_type": "file_here"
}
}
Because the course…
Source: GitHub Security Advisories (Global) 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-2026-27823 has been found in egroupware/egroupware.
Attackers can target a specific entry point like participant_role over the network to misuse the product.
Risk of unauthorized operations or information disclosure.
What to do: upgrade egroupware/egroupware to 23.1.20260224 or later.
If unsure, ask your IT team or search "egroupware/egroupware CVE-2026-27823" on the vendor's site.
CVE-2026-27823 (egroupware/egroupware) — CWE-22
Attack surface: participant_role / header.inc.php
Patched: 23.1.20260224 — 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 egroupware/egroupware. Attackers reach the vulnerable code path via participant_role.
Check the vendor advisory for the affected versions of egroupware/egroupware. Attack surface: participant_role / header.inc.php.
Severity: ?. Risk of unauthorized operations or information disclosure.
Update to 23.1.20260224.
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 'egroupware/egroupware' . 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 'egroupware/egroupware' . | 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
egroupware/egroupware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 egroupware/egroupware to 23.1.20260224ステージング環境で 23.1.20260224 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
- package github.com
- web github.com
- web github.com