CVE-2026-69207

Hono’s built-in CORS middleware (hono/cors) is vulnerable to a ReDoS in the Access-Control-Request-Headers parsing during preflight requests when allowHeaders is unset/empty. The regex-based parser can backtrack quadratically with long whitespace, potentially causing seconds of CPU usage per pref...

GHSA-8J4G-W8FX-2239 Hono: ReDoS in CORS middleware via Access-Control-Request-Headers

Summary The built-in CORS middleware hono/cors parses the attacker-controlled Access-Control-Request-Headers request header during a preflight OPTIONS request using a regular expression whose running time is quadratic in the input length. A single request carrying a long run of whitespace can...

EUVD-2025-23882

Malicious code in bioql PyPI...

GHSA-VH9X-PHQ6-FX54 Duplicate Advisory: Denial of service via malicious preflight requests in github.com/rs/cors

Duplicate Advisory This advisory has been withdrawn because it is a duplicate of GHSA-mh55-gqvf-xfwm. This link is maintained to preserve external references. Original Description Middleware causes a prohibitive amount of heap allocations when processing malicious preflight requests that include ...

CVE-2025-47908

Middleware causes a prohibitive amount of heap allocations when processing malicious preflight requests that include a Access-Control-Request-Headers ACRH header whose value contains many commas. This behavior can be abused by attackers to produce undue load on the middleware/server as an attempt...

UBUNTU-CVE-2025-47908

Middleware causes a prohibitive amount of heap allocations when processing malicious preflight requests that include a Access-Control-Request-Headers ACRH header whose value contains many commas. This behavior can be abused by attackers to produce undue load on the middleware/server as an attempt...

CVE-2025-47908 Denial of service via malicious preflight requests in github.com/rs/cors

Middleware causes a prohibitive amount of heap allocations when processing malicious preflight requests that include a Access-Control-Request-Headers ACRH header whose value contains many commas. This behavior can be abused by attackers to produce undue load on the middleware/server as an attempt...

CVE-2025-47908 Denial of service via malicious preflight requests in github.com/rs/cors

Middleware causes a prohibitive amount of heap allocations when processing malicious preflight requests that include a Access-Control-Request-Headers ACRH header whose value contains many commas. This behavior can be abused by attackers to produce undue load on the middleware/server as an attempt...

CVE-2025-47908

CVE-2025-47908 affects the Go middleware library github.com/rs/cors. Description in connected advisory confirms a DoS risk: processing malicious preflight requests with an Access-Control-Request-Headers header containing many commas triggers prohibitive heap allocations. Remediation provided by S...

CVE-2025-47908 Denial of service via malicious preflight requests in github.com/rs/cors

Middleware causes a prohibitive amount of heap allocations when processing malicious preflight requests that include a Access-Control-Request-Headers ACRH header whose value contains many commas. This behavior can be abused by attackers to produce undue load on the middleware/server as an attempt...

Denial of service via malicious preflight requests in github.com/rs/cors

Middleware causes a prohibitive amount of heap allocations when processing malicious preflight requests that include a Access-Control-Request-Headers ACRH header whose value contains many commas. This behavior can be abused by attackers to produce undue load on the middleware/server as an attempt...

PT-2025-32214

Name of the Vulnerable Software and Affected Versions Middleware affected versions not specified Description The middleware experiences excessive heap allocations when handling malicious preflight requests containing a large number of commas within the Access-Control-Request-Headers ACRH header...

CVE-2021-29431 SSRF in Sydent due to missing validation of hostnames

Sydent is a reference Matrix identity server. Sydent can be induced to send HTTP GET requests to internal systems, due to lack of parameter validation or IP address blacklisting. It is not possible to exfiltrate data or control request headers, but it might be possible to use the attack to perfor...