CVE-2026-33490: Use of Incorrectly-Resolved Name or Reference

H3 is a minimal HTTP framework. In versions 2.0.0-0 through 2.0.1-rc.16, the mount method in h3 uses a simple startsWith check to determine whether incoming requests fall under a mounted sub-application's path prefix. Because this check does not verify a path segment boundary i.e., that the next...

Open Redirect

Overview h3 is a Minimal HTTP framework built for high performance and portability. Affected versions of this package are vulnerable to Open Redirect via the redirectBack function. An attacker can cause users to be redirected to an external, attacker-controlled domain by crafting a URL with a...

GHSA-FP4X-GGRF-WMC6 H3 has an Open Redirect via Protocol-Relative Path in redirectBack() Referer Validation

Summary The redirectBack utility in h3 validates that the Referer header shares the same origin as the request before using its pathname as the redirect Location. However, the pathname is not sanitized for protocol-relative paths starting with //. An attacker can craft a same-origin URL with a...

H3 has an Open Redirect via Protocol-Relative Path in redirectBack() Referer Validation

Summary The redirectBack utility in h3 validates that the Referer header shares the same origin as the request before using its pathname as the redirect Location. However, the pathname is not sanitized for protocol-relative paths starting with //. An attacker can craft a same-origin URL with a...

@brendonovich/solidjs__start (>=0.0.0, <=0.0.3), @h3ravel/arquebus (>=0.3.3, <=0.6.6) +43 more potentially affected by CVE-2026-86250 via h3 (2.0.0-rc.1)

h3 NPM version 2.0.0-rc.1 is affected by a known vulnerability. The following packages have a transitive dependency on h3 and may be impacted: - @brendonovich/solidjsstart =0.0.0, =0.3.3, =0.1.0, =0.1.0, =0.1.0, =0.1.0, =0.1.0, =0.1.0, =0.1.0, =0.1.0, =0.1.0, =0.1.0, =0.1.0, =0.1.0, =0.3.0, =0.24...

Allocation of Resources Without Limits or Throttling

Overview h3 is a Minimal HTTP framework built for high performance and portability. Affected versions of this package are vulnerable to Allocation of Resources Without Limits or Throttling through the getChunkedCookieCount function. An attacker can cause the server to enter an inefficient cleanup...

@brendonovich/solidjs__start (>=0.0.0, <=0.0.3), @h3ravel/arquebus (>=0.3.3, <=0.6.6) +43 more potentially affected by unknown CVE via h3 (2.0.0-rc.1)

h3 NPM version 2.0.0-rc.1 is affected by a known vulnerability. The following packages have a transitive dependency on h3 and may be impacted: - @brendonovich/solidjsstart =0.0.0, =0.3.3, =0.1.0, =0.1.0, =0.1.0, =0.1.0, =0.1.0, =0.1.0, =0.1.0, =0.1.0, =0.1.0, =0.1.0, =0.1.0, =0.1.0, =0.3.0, =0.24...

CRLF Injection

Overview h3 is a Minimal HTTP framework built for high performance and portability. Affected versions of this package are vulnerable to CRLF Injection via unsanitized carriage return characters in the data and comment fields of the EventStream class. An attacker can inject arbitrary server-sent...

CRLF Injection

Overview org.webjars.npm:h3 is a Minimal HTTP framework built for high performance and portability. Affected versions of this package are vulnerable to CRLF Injection via unsanitized carriage return characters in the data and comment fields of the EventStream class. An attacker can inject arbitra...

@adpush/start (>=1.87.14, <=1.87.16), @akkuma/vinxi (0.3.12) +220 more potentially affected by unknown CVE via h3 (>=1.0.1, <=1.15.6)

h3 NPM version =1.0.1, =1.87.14, =1.0.7, =1.0.0, =1.5.0, =1.0.0, =0.8.16-canary.v20250123185645, =8.3.3, =3.1.0, =0.0.11, =3.1.0-0, =3.2.0 - @enrypase/solidstart-endpoint 0.1.0 and more Source cves: unknown CVE Source advisory: SNYK:JS-H3-15746329...

@brendonovich/solidjs__start (>=0.0.0, <=0.0.3), @h3ravel/arquebus (>=0.3.3, <=0.6.6) +43 more potentially affected by CVE-2026-86252 via h3 (2.0.0-rc.1)

h3 NPM version 2.0.0-rc.1 is affected by a known vulnerability. The following packages have a transitive dependency on h3 and may be impacted: - @brendonovich/solidjsstart =0.0.0, =0.3.3, =0.1.0, =0.1.0, =0.1.0, =0.1.0, =0.1.0, =0.1.0, =0.1.0, =0.1.0, =0.1.0, =0.1.0, =0.1.0, =0.1.0, =0.3.0, =0.24...

@adpush/start (>=1.87.14, <=1.87.16), @akkuma/vinxi (0.3.12) +220 more potentially affected by CVE-2026-86252 via h3 (>=1.0.1, <=1.15.6)

h3 NPM version =1.0.1, =1.87.14, =1.0.7, =1.0.0, =1.5.0, =1.0.0, =0.8.16-canary.v20250123185645, =8.3.3, =3.1.0, =0.0.11, =3.1.0-0, =3.2.0 - @enrypase/solidstart-endpoint 0.1.0 and more Source cves: CVE-2026-86252 Source advisory: OSV:GHSA-4HXC-9384-M385...

@brendonovich/solidjs__start (>=0.0.0, <=0.0.3), @h3ravel/arquebus (>=0.3.3, <=0.6.6) +43 more potentially affected by unknown CVE via h3 (2.0.0-rc.1)

h3 NPM version 2.0.0-rc.1 is affected by a known vulnerability. The following packages have a transitive dependency on h3 and may be impacted: - @brendonovich/solidjsstart =0.0.0, =0.3.3, =0.1.0, =0.1.0, =0.1.0, =0.1.0, =0.1.0, =0.1.0, =0.1.0, =0.1.0, =0.1.0, =0.1.0, =0.1.0, =0.1.0, =0.3.0, =0.24...

Use of Incorrectly-Resolved Name or Reference

Overview h3 is a Minimal HTTP framework built for high performance and portability. Affected versions of this package are vulnerable to Use of Incorrectly-Resolved Name or Reference via the mount method. An attacker can manipulate request context and set unintended privilege flags by crafting...

Directory Traversal

Overview org.webjars.npm:h3 is a Minimal HTTP framework built for high performance and portability. Affected versions of this package are vulnerable to Directory Traversal via the serveStatic utility. An attacker can access arbitrary files from backend storage by sending specially crafted request...

Directory Traversal

Overview h3 is a Minimal HTTP framework built for high performance and portability. Affected versions of this package are vulnerable to Directory Traversal via the serveStatic utility. An attacker can access arbitrary files from backend storage by sending specially crafted requests containing...

@adpush/start (>=1.87.14, <=1.87.16), @akkuma/vinxi (0.3.12) +220 more potentially affected by CVE-2026-86251 via h3 (>=1.0.1, <=1.15.6)

h3 NPM version =1.0.1, =1.87.14, =1.0.7, =1.0.0, =1.5.0, =1.0.0, =0.8.16-canary.v20250123185645, =8.3.3, =3.1.0, =0.0.11, =3.1.0-0, =3.2.0 - @enrypase/solidstart-endpoint 0.1.0 and more Source cves: CVE-2026-86251 Source advisory: OSV:GHSA-72GR-QFP7-VWHW...

@adpush/start (>=1.87.14, <=1.87.16), @akkuma/vinxi (0.3.12) +220 more potentially affected by unknown CVE via h3 (>=1.0.1, <=1.15.6)

h3 NPM version =1.0.1, =1.87.14, =1.0.7, =1.0.0, =1.5.0, =1.0.0, =0.8.16-canary.v20250123185645, =8.3.3, =3.1.0, =0.0.11, =3.1.0-0, =3.2.0 - @enrypase/solidstart-endpoint 0.1.0 and more Source cves: unknown CVE Source advisory: SNYK:JS-H3-15745711...

CVE-2026-33129

A flaw was found in H3, a minimal HTTP framework. A remote attacker can exploit a Timing Side-Channel vulnerability in the requireBasicAuth function. This vulnerability arises from the use of an unsafe string comparison, allowing the attacker to deduce valid passwords character-by-character by...

CVE-2026-33131

A flaw was found in H3, a minimal HTTP framework. When event.url, event.url.hostname, or event.url.url is accessed, such as in a logging middleware, the url getter constructs a URL from untrusted data, including the user-controlled Host header. Because H3's router resolves the route handler befor...