CVE-2026-1526: fallo de gravedad alta en undici
undici is vulnerable to Unbounded Memory Consumption in undici WebSocket permessage-deflate Decompression
Publicada el · Actualizada el
Aviso por correo cuando entre en el KEV, tenga PoC pública o suba de nota.
21Vexday Risk Score
Sin señal de explotación. Ningún artefacto público de explotación conocido hasta ahora.
ssvc Trackcvss 7.5epss 1.3%
The undici WebSocket client is vulnerable to a denial-of-service attack via unbounded memory consumption during permessage-deflate decompression. When a WebSocket connection negotiates the permessage-deflate extension, the client decompresses incoming compressed frames without enforcing any limit on the decompressed data size. A malicious WebSocket server can send a small compressed frame (a "decompression bomb") that expands to an extremely large size in memory, causing the Node.js process to exhaust available memory and crash or become unresponsive.
The vulnerability exists in the PerMessageDeflate.decompress() method, which accumulates all decompressed chunks in memory and concatenates them into a single Buffer without checking whether the total size exceeds a safe threshold.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Productos afectados
undici · undiciCVEs relacionadas — undici
En el mismo producto, de las más peligrosas a las menos.
CVE-2026-2229HIGHundici is vulnerable to Unhandled Exception in undici WebSocket Client Due to Invalid server_max_window_bits ValidationEPSS 1.0%CVE-2026-12151HIGHundici WebSocket client vulnerable to denial of service via fragment count bypassEPSS 0.8%CVE-2026-2581MEDIUMundici is vulnerable to Unbounded Memory Consumption in in Undici's DeduplicationHandler via Response Buffering leads to DoSEPSS 0.6%CVE-2026-13697HIGHundici vulnerable to cross-user information disclosure and parse-time crash via degenerate private cache directivesEPSS 0.6%CVE-2026-1528HIGHundici is vulnerable to Malicious WebSocket 64-bit length overflows undici parser and crashes the clientEPSS 0.6%CVE-2026-1525MEDIUMundici is vulnerable to Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')EPSS 0.6%
Referencias
https://access.redhat.com/errata/RHSA-2026:13826https://access.redhat.com/errata/RHSA-2026:17789https://access.redhat.com/errata/RHSA-2026:21772https://access.redhat.com/errata/RHSA-2026:21931https://access.redhat.com/errata/RHSA-2026:34342https://access.redhat.com/errata/RHSA-2026:56431https://access.redhat.com/errata/RHSA-2026:5807https://access.redhat.com/errata/RHSA-2026:7080https://access.redhat.com/errata/RHSA-2026:7123https://access.redhat.com/errata/RHSA-2026:7302https://access.redhat.com/errata/RHSA-2026:7310https://access.redhat.com/errata/RHSA-2026:7350