Path Traversal in Classroom (CVE-2026-94620)
Summary
Path traversal in Classroom (CVE-2026-94620). Risk of unauthorized operations or information disclosure. Exploitable via repo.
Original description
The description as published by the source.
Classroom 50 is a free and open-source tool for managing and grading programming assignments via GitHub. Prior to version 1.11.0, gh teacher download clones each student's assignment repository and then writes autograde artifacts (result.json and results.json) into the just-cloned working tree. The write followed symlinks, so a student who committed result.json or results.json as a symlink (materialized verbatim by git clone) could redirect the teacher's write to an arbitrary path — e.g. ~/.zshrc, ~/.ssh/authorized_keys, a cron file, or an in-clone .git/hooks/* file that git subsequently executes. The written bytes are attacker-controlled (the student's uploaded release asset for result.json; student-chosen submit-tag names for results.json). This is an arbitrary file write leading to code execution as the teacher, whose gh token carries admin:org, repo, and workflow across the entire classroom organization. Version 1.11.0 contains a patch. Some workarounds are available. Avoid running gh teacher download against untrusted student repositories, or run it inside a disposable sandbox / container with no access to sensitive host files or credentials. Inspect cloned trees for symlinked, hardlinked, or special (result.json/results.json) entries before allowing the artifact-refresh step to run.
Source: NIST National Vulnerability Database NVD
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-2026-94620 has been found in Classroom.
Attackers can target a specific entry point like repo over the network to misuse the product.
Risk of unauthorized operations or information disclosure.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Classroom CVE-2026-94620" on the vendor's site.
CVE-2026-94620 (Classroom) — CWE-22
Attack surface: repo / workflow
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 Classroom. Attackers reach the vulnerable code path via repo.
Check the vendor advisory for the affected versions of Classroom. Attack surface: repo / workflow.
Severity: ?. Risk of unauthorized operations or information disclosure.
Update to the patched release per vendor advisory.
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 'Classroom' . 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 'Classroom' . | 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
Classroomを grep し、稼働しているサービス・バージョンを把握する。 -
2Post-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。