restbed through 5.0.0 Denial of Service via Unbounded Header Buffering

Advisories

restbed through 5.0.0 Denial of Service via Unbounded Header Buffering

severity: high
date: 9/30/2026
Affecting: restbed <= 5.0.0
CVE: CVE-2026-103471
CWE: CWE-770 Allocation of Resources Without Limits or Throttling
CVSS: 8.7
CVSS V4 Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
References: GitHub Issue #558
https://github.com/Corvusoft/restbed
https://github.com/Corvusoft/restbed/blob/e1227a297ce6d4e9f78222456507b29bb8ab77e9/src/corvusoft/restbed/detail/service_impl.cpp#L554
https://github.com/Corvusoft/restbed/blob/e1227a297ce6d4e9f78222456507b29bb8ab77e9/src/corvusoft/restbed/session.cpp#L200
Credit: MJ DHURGESH
Description: restbed through 5.0.0 buffers HTTP request headers without enforcing a maximum size limit, allowing remote unauthenticated attackers to exhaust server memory. Attackers can open TCP connections and stream bytes indefinitely without sending the header delimiter, forcing the server to allocate unbounded heap memory until the process is killed.

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