PT-2026-70902 · Civetweb+2 · Civetweb

CVE-2026-29035

·

Published

2026-08-11

·

Updated

2026-08-11

CVSS v4.0

8.3

High

VectorAV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Name of the Vulnerable Software and Affected Versions CivetWeb version 4a4f0c95
Description A heap and stack buffer overflow exists in the read websocket() function. This occurs when both USE ZLIB and MG EXPERIMENTAL INTERFACES are defined. Unauthenticated remote attackers can corrupt memory by negotiating permessage-deflate during the WebSocket handshake and sending a crafted frame with the RSV1 bit set. This action causes the server to write a 4-byte zlib sync trailer out-of-bounds past the allocated buffer, which can lead to heap metadata corruption, denial of service, or potential code execution.
Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Memory Corruption

Found an issue in the description? Have something to add? Feel free to write us 👾

Weakness Enumeration

Related Identifiers

CVE-2026-29035

Affected Products

Civetweb