High · published March 13, 2026
ImpactA server can reply with a WebSocket frame using the 64-bit length form and an extremely large length. undici's ByteParser overflows internal math, ends up in an invalid state, and throws a fatal TypeError that terminates the process.
Patches
Patched in the undici version v7.24.0 and v6.24.0. Users should upgrade to this version or later.
| Product | Versions | Fixed in |
|---|---|---|
| nodejs/undici | < 6.24.0 | 6.24.0 |
| nodejs/undici | ≥ 7.0.0, < 7.24.0 | 7.24.0 |