{"id":"CVE-2026-45617","state":"PUBLISHED","title":"LiquidJS: ReDoS via Quadratic Backtracking in `strip_html` Filter Regex","description":"LiquidJS is a Shopify/GitHub Pages compatible template engine written in pure JavaScript. In versions 10.25.7 and below, the built-in strip_html filter uses a regex containing four flawed lazy-quantified alternatives, leading to ReDoS via quadratic backtracking. When the input contains many <script, <style, or <!-- opener tokens without matching closers, the V8 regex engine performs O(N²) backtracking, blocking the Node.js event loop. A single ~350 KB request ('<script'.repeat(50000)) stalls the process for ~10 seconds; cost grows quadratically with input size. The default memoryLimit: Infinity does not bound regex CPU, and even when configured strip_html only charges str.length to the limit — the regex itself runs unbounded.  A single unauthenticated request containing crafted untrusted input can cause severe event-loop blocking and CPU amplification that saturates Node.js workers while bypassing memoryLimit protections. This issue has been fixed in version 10.26.0.","publishedAt":"2026-06-17T22:14:38.396Z","updatedAt":"2026-06-18T15:46:28.241Z","severity":{"score":7.5,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","source":"GitHub_M"},"assigner":"GitHub_M","products":["harttle liquidjs"],"affected":[{"vendor":"harttle","product":"liquidjs","versions":[{"version":"< 10.26.0","status":"affected"}]}],"references":["https://github.com/harttle/liquidjs/security/advisories/GHSA-r7g9-xpmj-5fcq","https://github.com/harttle/liquidjs/commit/3616a744b9abeb425c217b340a2397d46176afb8","https://github.com/harttle/liquidjs/releases/tag/v10.26.0"],"weaknesses":["CWE-1333"],"ingestedAt":"2026-10-29T20:12:07.131Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/45xxx/CVE-2026-45617.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-45617","state":"PUBLISHED","datePublished":"2026-06-17T22:14:38.396Z","dateUpdated":"2026-06-18T15:46:28.241Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-05-12T20:31:43.448Z"},"containers":{"cna":{"title":"LiquidJS: ReDoS via Quadratic Backtracking in `strip_html` Filter Regex","descriptions":[{"lang":"en","value":"LiquidJS is a Shopify/GitHub Pages compatible template engine written in pure JavaScript. In versions 10.25.7 and below, the built-in strip_html filter uses a regex containing four flawed lazy-quantified alternatives, leading to ReDoS via quadratic backtracking. When the input contains many <script, <style, or <!-- opener tokens without matching closers, the V8 regex engine performs O(N²) backtracking, blocking the Node.js event loop. A single ~350 KB request ('<script'.repeat(50000)) stalls the process for ~10 seconds; cost grows quadratically with input size. The default memoryLimit: Infinity does not bound regex CPU, and even when configured strip_html only charges str.length to the limit — the regex itself runs unbounded.  A single unauthenticated request containing crafted untrusted input can cause severe event-loop blocking and CPU amplification that saturates Node.js workers while bypassing memoryLimit protections. This issue has been fixed in version 10.26.0."}],"affected":[{"vendor":"harttle","product":"liquidjs","versions":[{"version":"< 10.26.0","status":"affected"}]}],"references":[{"url":"https://github.com/harttle/liquidjs/security/advisories/GHSA-r7g9-xpmj-5fcq","name":"https://github.com/harttle/liquidjs/security/advisories/GHSA-r7g9-xpmj-5fcq","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/harttle/liquidjs/commit/3616a744b9abeb425c217b340a2397d46176afb8","name":"https://github.com/harttle/liquidjs/commit/3616a744b9abeb425c217b340a2397d46176afb8","tags":["x_refsource_MISC"]},{"url":"https://github.com/harttle/liquidjs/releases/tag/v10.26.0","name":"https://github.com/harttle/liquidjs/releases/tag/v10.26.0","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":7.5,"baseSeverity":"HIGH","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-1333","lang":"en","description":"CWE-1333: Inefficient Regular Expression Complexity","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-06-17T22:14:38.396Z"},"source":{"advisory":"GHSA-r7g9-xpmj-5fcq","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/harttle/liquidjs/security/advisories/GHSA-r7g9-xpmj-5fcq","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-06-18T15:46:01.767622Z","id":"CVE-2026-45617","options":[{"Exploitation":"poc"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-06-18T15:46:28.241Z"}}]}}}