{"schema_version":1,"title":"h3 (npm) vulnerabilities","summary":"Junglewise Threat Intelligence has tracked 10 vulnerabilities in h3 (npm): 0 in the last 7 days and 5 in the last 90 days, 0 of them critical and 0 exploited in the wild. The most recent, CVE-2026-86253, was published on 6 September 2026.","url":"https://junglewise.ai/threats/technologies/h3","json_url":"https://junglewise.ai/threats/technologies/h3.json","publisher":"Junglewise Threat Intelligence","license":"CC-BY-4.0","license_url":"https://creativecommons.org/licenses/by/4.0/","attribution":"Junglewise Threat Intelligence, https://junglewise.ai/threats/technologies/h3","sources":"NVD, GitHub Security Advisories, OSV, the CISA Known Exploited Vulnerabilities catalog, FIRST EPSS and vendor advisories","kind":"technology","counts":{"high":2,"all_time":10,"critical":0,"exploited":0,"last_7_days":0,"last_30_days":5,"last_90_days":5,"last_365_days":10},"latest":[{"cve":"CVE-2026-86253","cvss":5.9,"epss":0.0062,"slug":"cve-2026-86253-h3-servestatic-path-traversal-via-percent-encoded-dot-segments","title":"h3 (npm package) versions <= 2.0.1-rc.14 contain a path traversal vulnerability in serveStatic(). On Node.js deployments, event.url.pathname","severity":"medium","exploited":false,"published_at":"2026-09-06T12:17:16.163+00:00","url":"https://junglewise.ai/threats/cve-2026-86253-h3-servestatic-path-traversal-via-percent-encoded-dot-segments"},{"cve":"CVE-2026-86252","cvss":5.3,"epss":0.0036,"slug":"cve-2026-86252-h3-sse-event-injection-via-unsanitized-carriage-return","title":"h3 versions before 1.15.9 fail to sanitize carriage return characters in EventStream data and comment fields, allowing attackers to inject a","severity":"medium","exploited":false,"published_at":"2026-09-06T12:17:16.033+00:00","url":"https://junglewise.ai/threats/cve-2026-86252-h3-sse-event-injection-via-unsanitized-carriage-return"},{"cve":"CVE-2026-86251","cvss":5.9,"epss":0.0043,"slug":"cve-2026-86251-h3-servestatic-path-traversal-via-double-encoded-dot-segments","title":"h3 versions before 1.15.9 contain a path traversal vulnerability in the serveStatic utility. A double-decoding flaw allows a request path co","severity":"medium","exploited":false,"published_at":"2026-09-06T12:17:15.9+00:00","url":"https://junglewise.ai/threats/cve-2026-86251-h3-servestatic-path-traversal-via-double-encoded-dot-segments"},{"cve":"CVE-2026-86250","cvss":7.5,"epss":0.0049,"slug":"cve-2026-86250-h3-unbounded-chunked-cookie-denial-of-service","title":"h3 versions before 2.0.1-rc.18 fail to validate the chunk count parsed from user-controlled cookie values in setChunkedCookie() and deleteCh","severity":"high","exploited":false,"published_at":"2026-09-06T12:17:15.767+00:00","url":"https://junglewise.ai/threats/cve-2026-86250-h3-unbounded-chunked-cookie-denial-of-service"},{"cve":"CVE-2026-86205","cvss":5.4,"epss":0.0027,"slug":"cve-2026-86205-h3-open-redirect-via-protocol-relative-path-in-redirectback","title":"h3 versions before 2.0.1-rc.18 contain an open redirect vulnerability in the redirectBack() utility that fails to sanitize protocol-relative","severity":"medium","exploited":false,"published_at":"2026-09-06T12:17:15.277+00:00","url":"https://junglewise.ai/threats/cve-2026-86205-h3-open-redirect-via-protocol-relative-path-in-redirectback"},{"cve":"CVE-2026-33490","cvss":3.1,"epss":0.0028,"slug":"cve-2026-33490-h3js-h3-incorrect-path-validation-in-mount-method","title":"h3 missing path segment boundary check in mount()","severity":"low","exploited":false,"published_at":"2026-03-20T20:50:27+00:00","url":"https://junglewise.ai/threats/cve-2026-33490-h3js-h3-incorrect-path-validation-in-mount-method"},{"cve":"CVE-2026-33131","cvss":3.1,"epss":0.0044,"slug":"cve-2026-33131-h3js-h3-middleware-bypass-via-host-header-spoofing","title":"h3 middleware bypass via Host header spoofing","severity":"low","exploited":false,"published_at":"2026-03-18T16:18:12+00:00","url":"https://junglewise.ai/threats/cve-2026-33131-h3js-h3-middleware-bypass-via-host-header-spoofing"},{"cve":"CVE-2026-33129","cvss":3.1,"epss":0.0045,"slug":"cve-2026-33129-h3js-h3-timing-side-channel-in-requirebasicauth","title":"h3 timing side-channel in basic auth validation","severity":"low","exploited":false,"published_at":"2026-03-18T16:17:58+00:00","url":"https://junglewise.ai/threats/cve-2026-33129-h3js-h3-timing-side-channel-in-requirebasicauth"},{"cve":"CVE-2026-33128","cvss":3.1,"epss":0.0069,"slug":"cve-2026-33128-h3js-h3-server-sent-events-injection-in-createeventstream","title":"h3 Server-Sent Events injection via unsanitized newlines","severity":"low","exploited":false,"published_at":"2026-03-18T16:17:43+00:00","url":"https://junglewise.ai/threats/cve-2026-33128-h3js-h3-server-sent-events-injection-in-createeventstream"},{"cve":"CVE-2026-23527","cvss":8.9,"epss":0.0064,"slug":"cve-2026-23527-h3js-h3-http-request-smuggling-in-readrawbody","title":"h3js h3 HTTP request smuggling in readRawBody","severity":"high","exploited":false,"published_at":"2026-01-15T20:10:51+00:00","url":"https://junglewise.ai/threats/cve-2026-23527-h3js-h3-http-request-smuggling-in-readrawbody"}],"weekly":[{"week":"2026-06-29","critical":0,"exploited":0,"vulnerabilities":0},{"week":"2026-07-06","critical":0,"exploited":0,"vulnerabilities":0},{"week":"2026-07-13","critical":0,"exploited":0,"vulnerabilities":0},{"week":"2026-07-20","critical":0,"exploited":0,"vulnerabilities":0},{"week":"2026-07-27","critical":0,"exploited":0,"vulnerabilities":0},{"week":"2026-08-03","critical":0,"exploited":0,"vulnerabilities":0},{"week":"2026-08-10","critical":0,"exploited":0,"vulnerabilities":0},{"week":"2026-08-17","critical":0,"exploited":0,"vulnerabilities":0},{"week":"2026-08-24","critical":0,"exploited":0,"vulnerabilities":0},{"week":"2026-08-31","critical":0,"exploited":0,"vulnerabilities":5},{"week":"2026-09-07","critical":0,"exploited":0,"vulnerabilities":0},{"week":"2026-09-14","critical":0,"exploited":0,"vulnerabilities":0},{"week":"2026-09-21","critical":0,"exploited":0,"vulnerabilities":0}],"related":[{"name":"flowise (npm)","slug":"flowise","vulnerabilities":156,"url":"https://junglewise.ai/threats/technologies/flowise"},{"name":"vm2 (npm)","slug":"vm2","vulnerabilities":83,"url":"https://junglewise.ai/threats/technologies/vm2"},{"name":"@budibase/server (npm)","slug":"budibase-server","vulnerabilities":61,"url":"https://junglewise.ai/threats/technologies/budibase-server"},{"name":"directus (npm)","slug":"directus","vulnerabilities":60,"url":"https://junglewise.ai/threats/technologies/directus"},{"name":"nocodb (npm)","slug":"nocodb","vulnerabilities":55,"url":"https://junglewise.ai/threats/technologies/nocodb"},{"name":"hono (npm)","slug":"hono","vulnerabilities":54,"url":"https://junglewise.ai/threats/technologies/hono"},{"name":"parse-server (npm)","slug":"parse-server","vulnerabilities":42,"url":"https://junglewise.ai/threats/technologies/parse-server"},{"name":"dompurify (npm)","slug":"dompurify","vulnerabilities":39,"url":"https://junglewise.ai/threats/technologies/dompurify"},{"name":"ghost (npm)","slug":"ghost","vulnerabilities":39,"url":"https://junglewise.ai/threats/technologies/ghost"},{"name":"flowise-components (npm)","slug":"flowise-components","vulnerabilities":35,"url":"https://junglewise.ai/threats/technologies/flowise-components"},{"name":"astro (npm)","slug":"astro","vulnerabilities":30,"url":"https://junglewise.ai/threats/technologies/astro"},{"name":"@anthropic-ai/claude-code (npm)","slug":"anthropic-ai-claude-code","vulnerabilities":28,"url":"https://junglewise.ai/threats/technologies/anthropic-ai-claude-code"}],"technology":{"hub":true,"name":"h3 (npm)","slug":"h3","vendor":{"name":"npm","slug":"npm","url":"https://junglewise.ai/threats/vendors/npm"},"aliases":[],"homepage":"https://h3.unjs.io/","repo_url":"https://github.com/unjs/h3","description":"A high-performance HTTP framework and server engine for Node.js.","url":"https://junglewise.ai/threats/technologies/h3"},"most_severe":[{"cve":"CVE-2026-23527","cvss":8.9,"epss":0.0064,"slug":"cve-2026-23527-h3js-h3-http-request-smuggling-in-readrawbody","title":"h3js h3 HTTP request smuggling in readRawBody","severity":"high","exploited":false,"published_at":"2026-01-15T20:10:51+00:00","url":"https://junglewise.ai/threats/cve-2026-23527-h3js-h3-http-request-smuggling-in-readrawbody"},{"cve":"CVE-2026-86250","cvss":7.5,"epss":0.0049,"slug":"cve-2026-86250-h3-unbounded-chunked-cookie-denial-of-service","title":"h3 versions before 2.0.1-rc.18 fail to validate the chunk count parsed from user-controlled cookie values in setChunkedCookie() and deleteCh","severity":"high","exploited":false,"published_at":"2026-09-06T12:17:15.767+00:00","url":"https://junglewise.ai/threats/cve-2026-86250-h3-unbounded-chunked-cookie-denial-of-service"},{"cve":"CVE-2026-86253","cvss":5.9,"epss":0.0062,"slug":"cve-2026-86253-h3-servestatic-path-traversal-via-percent-encoded-dot-segments","title":"h3 (npm package) versions <= 2.0.1-rc.14 contain a path traversal vulnerability in serveStatic(). On Node.js deployments, event.url.pathname","severity":"medium","exploited":false,"published_at":"2026-09-06T12:17:16.163+00:00","url":"https://junglewise.ai/threats/cve-2026-86253-h3-servestatic-path-traversal-via-percent-encoded-dot-segments"},{"cve":"CVE-2026-86251","cvss":5.9,"epss":0.0043,"slug":"cve-2026-86251-h3-servestatic-path-traversal-via-double-encoded-dot-segments","title":"h3 versions before 1.15.9 contain a path traversal vulnerability in the serveStatic utility. A double-decoding flaw allows a request path co","severity":"medium","exploited":false,"published_at":"2026-09-06T12:17:15.9+00:00","url":"https://junglewise.ai/threats/cve-2026-86251-h3-servestatic-path-traversal-via-double-encoded-dot-segments"},{"cve":"CVE-2026-86205","cvss":5.4,"epss":0.0027,"slug":"cve-2026-86205-h3-open-redirect-via-protocol-relative-path-in-redirectback","title":"h3 versions before 2.0.1-rc.18 contain an open redirect vulnerability in the redirectBack() utility that fails to sanitize protocol-relative","severity":"medium","exploited":false,"published_at":"2026-09-06T12:17:15.277+00:00","url":"https://junglewise.ai/threats/cve-2026-86205-h3-open-redirect-via-protocol-relative-path-in-redirectback"},{"cve":"CVE-2026-86252","cvss":5.3,"epss":0.0036,"slug":"cve-2026-86252-h3-sse-event-injection-via-unsanitized-carriage-return","title":"h3 versions before 1.15.9 fail to sanitize carriage return characters in EventStream data and comment fields, allowing attackers to inject a","severity":"medium","exploited":false,"published_at":"2026-09-06T12:17:16.033+00:00","url":"https://junglewise.ai/threats/cve-2026-86252-h3-sse-event-injection-via-unsanitized-carriage-return"},{"cve":"CVE-2026-33128","cvss":3.1,"epss":0.0069,"slug":"cve-2026-33128-h3js-h3-server-sent-events-injection-in-createeventstream","title":"h3 Server-Sent Events injection via unsanitized newlines","severity":"low","exploited":false,"published_at":"2026-03-18T16:17:43+00:00","url":"https://junglewise.ai/threats/cve-2026-33128-h3js-h3-server-sent-events-injection-in-createeventstream"},{"cve":"CVE-2026-33129","cvss":3.1,"epss":0.0045,"slug":"cve-2026-33129-h3js-h3-timing-side-channel-in-requirebasicauth","title":"h3 timing side-channel in basic auth validation","severity":"low","exploited":false,"published_at":"2026-03-18T16:17:58+00:00","url":"https://junglewise.ai/threats/cve-2026-33129-h3js-h3-timing-side-channel-in-requirebasicauth"},{"cve":"CVE-2026-33131","cvss":3.1,"epss":0.0044,"slug":"cve-2026-33131-h3js-h3-middleware-bypass-via-host-header-spoofing","title":"h3 middleware bypass via Host header spoofing","severity":"low","exploited":false,"published_at":"2026-03-18T16:18:12+00:00","url":"https://junglewise.ai/threats/cve-2026-33131-h3js-h3-middleware-bypass-via-host-header-spoofing"},{"cve":"CVE-2026-33490","cvss":3.1,"epss":0.0028,"slug":"cve-2026-33490-h3js-h3-incorrect-path-validation-in-mount-method","title":"h3 missing path segment boundary check in mount()","severity":"low","exploited":false,"published_at":"2026-03-20T20:50:27+00:00","url":"https://junglewise.ai/threats/cve-2026-33490-h3js-h3-incorrect-path-validation-in-mount-method"}],"generated_at":"2026-09-27T03:07:00.185062+00:00"}