CVE-2026-34752

ImpactThe undici WebSocket client is vulnerable to a denial-of-service attack due to improper validation of the server_max_window_bits parameter in the permessage-deflate extension. When a WebSocket client connects to a server, it automatically advertises support for permessage-deflate compression. A malicious server can respond with an out-of-range server_max_window_bits value (outside zlib's valid range of 8-15). When the server subsequently sends a compressed frame, the client attempts to create a zlib InflateRaw instance with the invalid windowBits value, causing a synchronous RangeError exception that is not caught, resulting in immediate process termination. The vulnerability exists because: * The isValidClientWindowBits() function only validates that the value contains ASCII digits, not that it falls within the valid range 8-15 * The createInflateRaw() call is not wrapped in a try-catch block * The resulting exception propagates up through the call stack and crashes the Node.js process

Excelize is a Go language library for reading and writing Microsoft Excel spreadsheets. Prior to 2.11.0, Excelize parses shared-string cell values with strconv.Atoi and checks only the upper bound before indexing the shared string slice, allowing an XLSX file containing a shared-string cell with -1 to trigger sharedStrings[-1] and panic when read through GetCellValue or GetRows. This issue is fixed in version 2.11.0.

Go JOSE provides an implementation of the Javascript Object Signing and Encryption set of standards in Go, including support for JSON Web Encryption (JWE), JSON Web Signature (JWS), and JSON Web Token (JWT) standards. Prior to 4.1.4 and 3.0.5, decrypting a JSON Web Encryption (JWE) object will panic if the alg field indicates a key wrapping algorithm (one ending in KW, with the exception of A128GCMKW, A192GCMKW, and A256GCMKW) and the encrypted_key field is empty. The panic happens when cipher.KeyUnwrap() in key_wrap.go attempts to allocate a slice with a zero or negative length based on the length of the encrypted_key. This code path is reachable from ParseEncrypted() / ParseEncryptedJSON() / ParseEncryptedCompact() followed by Decrypt() on the resulting object. Note that the parse functions take a list of accepted key algorithms. If the accepted key algorithms do not include any key wrapping algorithms, parsing will fail and the application will be unaffected. This panic is also reachable by calling cipher.KeyUnwrap() directly with any ciphertext parameter less than 16 bytes long, but calling this function directly is less common. Panics can lead to denial of service. This vulnerability is fixed in 4.1.4 and 3.0.5.

@grpc/grps-js implements the core functionality of gRPC purely in JavaScript, without a C++ addon. Prior to 1.9.16, 1.10.12, 1.11.4, 1.12.7, 1.13.5, and 1.14.4, an invalid incoming compressed message can cause a client or server process that uses @grpc/grpc-js to crash. This issue is fixed in versions 1.9.16, 1.10.12, 1.11.4, 1.12.7, 1.13.5, and 1.14.4.

@grpc/grps-js implements the core functionality of gRPC purely in JavaScript, without a C++ addon. Prior to 1.9.16, 1.10.12, 1.11.4, 1.12.7, 1.13.5, and 1.14.4, an invalid incoming HTTP/2 stream initiation can cause a server process created using @grpc/grpc-js to crash. This issue is fixed in versions 1.9.16, 1.10.12, 1.11.4, 1.12.7, 1.13.5, and 1.14.4.

NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.14.3 and 2.12.12, a WebSocket listener could route requests for the MQTT-over-WebSocket path into MQTT handling even when MQTT was not configured, allowing an unauthenticated client with access to the WebSocket listener to reach uninitialized MQTT state and crash the server process. This issue is fixed in versions 2.14.3 and 2.12.12.