Vulnerability in python-liquid (CVE-2026-55865)
Summary
Vulnerability in python-liquid (CVE-2026-55865). Risk of unauthorized operations or information disclosure. Exploitable via liquid.TokenStream.eof. Mitigation: upgrade to 2.2.1 or later.
Original description
The description as published by the source.
Impact
Given a malformed {% case %} tag without associated {% when %} or {% else %} block, and no terminating {% endcase %} tag, Python Liquid hangs in an infinite loop at parse time. This allows malicious template authors to craft templates for a denial of service attack.
Patches
The issue is fixed in version 2.2.1 with the correction of the liquid.TokenStream.eof attribute. The kind and value of the special EOF token are now the same, so either can be tested against liquid.token.TOKEN_EOF.
Workarounds
Manually correct the definition of liquid.TokenStream.eof before parsing any templates.
import liquid
from liquid.token import TOKEN_EOF
liquid.stream.TokenStream.eof = liquid.Token(TOKEN_EOF, TOKEN_EOF, -1, "")
# ...
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-2026-55865 has been found in python-liquid.
Attackers can target a specific entry point like liquid.TokenStream.eof over the network to misuse the product.
Risk of unauthorized operations or information disclosure.
What to do: upgrade python-liquid to 2.2.1 or later.
If unsure, ask your IT team or search "python-liquid CVE-2026-55865" on the vendor's site.
CVE-2026-55865 (python-liquid) — CWE-835
Attack surface: liquid.TokenStream.eof / kind / value / liquid.token.TOKEN_EOF
Patched: 2.2.1 — 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.
A vulnerability (CWE-835) exists in python-liquid. Attackers reach the vulnerable code path via liquid.TokenStream.eof.
Check the vendor advisory for the affected versions of python-liquid. Attack surface: liquid.TokenStream.eof / kind / value / liquid.token.TOKEN_EOF.
Severity: ?. Risk of unauthorized operations or information disclosure.
Update to 2.2.1.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'python-liquid' . 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 'python-liquid' . | 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
python-liquid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 python-liquid to 2.2.1ステージング環境で 2.2.1 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。