Unsafe Deserialization in apache-airflow (CVE-2026-59242)
Summary
Vulnerability in apache-airflow (CVE-2026-59242). Risk of unauthorized operations or information disclosure. Exploitable via GET /api/v2/{...}/xcomEntries/{key}. Mitigation: upgrade to 3.3.1 or later.
Original description
The description as published by the source.
Apache Airflow's XCom GET /api/v2/{...}/xcomEntries/{key}?deserialize=true endpoint passed a string-literal payload through BaseXCom.deserialize_value without the _check_forbidden_xcom_keys guard, allowing an authenticated API user with XCom write-and-read access to instantiate arbitrary airflow.* classes on the API server (CWE-502). An authenticated user who can write an XCom value and then read it back with deserialize=true triggers the unsafe instantiation. Users are advised to upgrade to apache-airflow 3.3.1 or later, which rejects reserved XCom serialization keys submitted as JSON string literals.
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-2026-59242 has been found in apache-airflow.
Attackers can target a specific entry point like GET /api/v2/{...}/xcomEntries/{key} over the network to misuse the product.
Risk of unauthorized operations or information disclosure. CVSS score: 5.4/10.
What to do: upgrade apache-airflow to 3.3.1 or later.
If unsure, ask your IT team or search "apache-airflow CVE-2026-59242" on the vendor's site.
CVE-2026-59242 (apache-airflow) — CWE-502 / CVSS v3 5.4
Attack vector: remote (network-reachable) / no user interaction
Attack surface: GET /api/v2/{...}/xcomEntries/{key} / BaseXCom.deserialize_value / _check_forbidden_xcom_keys
Patched: 3.3.1 — 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.
Unsafe deserialization (CWE-502) exists in apache-airflow. Attackers reach the vulnerable code path via GET /api/v2/{...}/xcomEntries/{key}.
Check the vendor advisory for the affected versions of apache-airflow. Attack surface: GET /api/v2/{...}/xcomEntries/{key} / BaseXCom.deserialize_value / _check_forbidden_xcom_keys.
Severity: Medium (CVSS 5.4/10). Risk of unauthorized operations or information disclosure.
Update to 3.3.1.
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/v2/{...}/xcomEntries/{key} requests with malformed payloads or SQL meta-characters. Run grep -r 'apache-airflow' . 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 'apache-airflow' . | 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
apache-airflow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/v2/{...}/xcomEntries/{key}' /var/log/nginx/access.log | grep -E '(unusual_payload|sqli_pattern)'アクセスログで
GET /api/v2/{...}/xcomEntries/{key}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 apache-airflow to 3.3.1ステージング環境で 3.3.1 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/v2/{...}/xcomEntries/{key} 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 lists.apache.org
- advisory nvd.nist.gov
- advisory openwall.com
- advisory github.com
- package github.com
- patch github.com
- web github.com
- web github.com
- web github.com
- web github.com