CVE-2026-16117

The CVE concerns @fastify/http-proxy (affected: up to 11.5.0) where URL prefix rewriting fails when the prefix segment is URL-encoded. Fastify decodes paths for route matching, but request.url keeps the original encoded form. The prefixRewrite step compares against the decoded prefix using a lite...

CVE-2026-16117 @fastify/http-proxy vulnerable to prefix escape via URL-encoded characters

Impact: @fastify/http-proxy versions up to and including 11.5.0 fail to rewrite the request prefix when the prefix segment is URL-encoded. Fastify's router URL-decodes paths for route matching, but request.url retains the original encoded form, and the prefix-rewrite step uses a literal string...

@agentspec/claude-plugin (>=0.1.0, <=0.2.0), @agentspec/sidecar (0.1.0) +108 more potentially affected by CVE-2026-16117 via @fastify/http-proxy (>=7.1.0, <=11.5.0)

@fastify/http-proxy NPM version =7.1.0, =0.1.0, =0.0.2, =1.0.19, =2.1.22, =0.1.1, =0.1.0, =0.0.4, =0.0.4, =6.0.0-canary.2685, =0.0.4, =0.0.4, =4.0.0-canary.13864, =4.0.0-canary.13864, =6.0.0-canary.2746 and more Source cves: CVE-2026-16117 Source advisory: MEND:CVE-2026-16117...

EUVD-2026-45379

Impact: @fastify/http-proxy versions up to and including 11.5.0 fail to rewrite the request prefix when the prefix segment is URL-encoded. Fastify's router URL-decodes paths for route matching, but request.url retains the original encoded form, and the prefix-rewrite step uses a literal string...

CVE-2026-15631

Impact: @fastify/http-proxy versions from 9.4.0 up to and including 11.5.0 fail to validate the resolved WebSocket destination path against the configured rewrite prefix. The WebSocket routing path in WebSocketProxy.findUpstream resolves the destination via the WHATWG URL constructor, which...

@agentspec/claude-plugin (>=0.1.0, <=0.2.0), @agentspec/sidecar (0.1.0) +87 more potentially affected by CVE-2026-15631 via @fastify/http-proxy (>=9.4.0, <=11.5.0)

@fastify/http-proxy NPM version =9.4.0, =0.1.0, =1.0.19, =2.1.22, =0.1.1, =0.1.0, =0.0.4, =0.0.4, =6.0.0-canary.2685, =0.0.4, =0.0.4, =4.0.0-canary.13864, =4.0.0-canary.13864, =0.0.4, =9.0.0-canary.1784 and more Source cves: CVE-2026-15631 Source advisory: MEND:CVE-2026-15631...

CVE-2026-15631 @fastify/http-proxy vulnerable to prefix escape via WebSocket path traversal

Impact: @fastify/http-proxy versions from 9.4.0 up to and including 11.5.0 fail to validate the resolved WebSocket destination path against the configured rewrite prefix. The WebSocket routing path in WebSocketProxy.findUpstream resolves the destination via the WHATWG URL constructor, which...

CVE-2026-15631 @fastify/http-proxy vulnerable to prefix escape via WebSocket path traversal

Impact: @fastify/http-proxy versions from 9.4.0 up to and including 11.5.0 fail to validate the resolved WebSocket destination path against the configured rewrite prefix. The WebSocket routing path in WebSocketProxy.findUpstream resolves the destination via the WHATWG URL constructor, which...

CVE-2026-15631 @fastify/http-proxy vulnerable to prefix escape via WebSocket path traversal

Impact: @fastify/http-proxy versions from 9.4.0 up to and including 11.5.0 fail to validate the resolved WebSocket destination path against the configured rewrite prefix. The WebSocket routing path in WebSocketProxy.findUpstream resolves the destination via the WHATWG URL constructor, which...

EUVD-2026-45375

Impact: @fastify/http-proxy versions from 9.4.0 up to and including 11.5.0 fail to validate the resolved WebSocket destination path against the configured rewrite prefix. The WebSocket routing path in WebSocketProxy.findUpstream resolves the destination via the WHATWG URL constructor, which...

CVE-2026-15631

Summary (supported by provided sources): The CVE-2026-15631 issue affects @fastify/http-proxy versions 9.4.0 to 11.5.0, where the WebSocket routing logic in WebSocketProxy.findUpstream validates the destination path against the rewrite prefix but relies on the WHATWG URL constructor, which collap...

CVE-2026-16158

CVE-2026-16158 affects @fastify/reply-from. The vulnerability stems from how the internal URL cache key is built by concatenating the destination and source paths without a delimiter in versions 8.3.1 up to (but not including) 12.6.4. This can cause key collisions where different upstreams resolv...

CVE-2026-16158 @fastify/reply-from vulnerable to cross-upstream request routing via URL cache key collision

Impact: @fastify/reply-from versions from 8.3.1 up to but not including 12.6.4 build the internal URL cache key by concatenating the destination and source path without a delimiter. Different destination and source pairs can therefore produce the same key while resolving to different upstream URL...

@agentspec/claude-plugin (>=0.1.0, <=0.2.0), @agentspec/sidecar (0.1.0) +85 more potentially affected by CVE-2026-16158 via @fastify/reply-from (>=8.3.1, <=11.0.2)

@fastify/reply-from NPM version =8.3.1, =0.1.0, =0.0.2, =1.0.0, =1.0.19, =2.1.22, =0.1.1, =0.1.0, =0.0.4, =0.0.4, =0.0.4, =0.0.4, =0.0.4, =1.0.0, =1.0.1 and more Source cves: CVE-2026-16158 Source advisory: MEND:CVE-2026-16158...

CVE-2026-16158

Impact: @fastify/reply-from versions from 8.3.1 up to but not including 12.6.4 build the internal URL cache key by concatenating the destination and source path without a delimiter. Different destination and source pairs can therefore produce the same key while resolving to different upstream URL...

CVE-2026-16158 @fastify/reply-from vulnerable to cross-upstream request routing via URL cache key collision

Impact: @fastify/reply-from versions from 8.3.1 up to but not including 12.6.4 build the internal URL cache key by concatenating the destination and source path without a delimiter. Different destination and source pairs can therefore produce the same key while resolving to different upstream URL...

EUVD-2026-45373

Impact: @fastify/reply-from versions from 8.3.1 up to but not including 12.6.4 build the internal URL cache key by concatenating the destination and source path without a delimiter. Different destination and source pairs can therefore produce the same key while resolving to different upstream URL...

PT-2026-60960

Name of the Vulnerable Software and Affected Versions @fastify/http-proxy versions 9.4.0 through 11.5.0 Description WebSocket destination paths are not properly validated against the configured rewrite prefix. The WebSocketProxy.findUpstream function resolves destinations using the WHATWG URL...

CVE-2026-16117: Improper Input Validation

Impact: @fastify/http-proxy versions up to and including 11.5.0 fail to rewrite the request prefix when the prefix segment is URL-encoded. Fastify's router URL-decodes paths for route matching, but request.url retains the original encoded form, and the prefix-rewrite step uses a literal string...

PT-2026-60961

Name of the Vulnerable Software and Affected Versions @fastify/http-proxy versions prior to 11.6.0 Description An improper input normalization issue exists where the software fails to rewrite the request prefix when the prefix segment is URL-encoded. While the router URL-decodes paths for route...