In lighttpd 1.4.65, mod_wstunnel does not initialize a handler function pointer if an invalid HTTP request (websocket handshake) is received. It leads to null pointer dereference which crashes the server. It could be used by an external attacker to cause denial of service condition.
Weakness
The product dereferences a pointer that it expects to be valid but is NULL.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Lighttpd | Lighttpd | 1.4.65 (including) | 1.4.65 (including) |
| Lighttpd | Ubuntu | esm-apps/focal | * |
| Lighttpd | Ubuntu | esm-apps/jammy | * |
| Lighttpd | Ubuntu | focal | * |
| Lighttpd | Ubuntu | jammy | * |
| Lighttpd | Ubuntu | kinetic | * |
| Lighttpd | Ubuntu | lunar | * |
| Lighttpd | Ubuntu | trusty | * |
| Lighttpd | Ubuntu | upstream | * |
| Lighttpd | Ubuntu | xenial | * |
Potential Mitigations
References
- https://lists.debian.org/debian-lts-announce/2022/10/msg00002.html
- https://redmine.lighttpd.net/issues/3165
- https://security.gentoo.org/glsa/202210-12
- https://www.debian.org/security/2022/dsa-5243
- https://lists.debian.org/debian-lts-announce/2022/10/msg00002.html
- https://redmine.lighttpd.net/issues/3165
- https://security.gentoo.org/glsa/202210-12
- https://www.debian.org/security/2022/dsa-5243