SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2026-35665

An unauthenticated attacker can exhaust server connection resources by sending concurrent slow HTTP POST requests to the Feishu webhook endpoint, blocking legitimate webhook deliveries.

MEDIUM 6.9EPSS 0.33%

Does this matter?

Lower severity and a low EPSS score (0.33%). Track it; it rarely justifies an emergency change on its own.

Description

OpenClaw before 2026.3.24 contains an incomplete fix for CVE-2026-32011 where the Feishu webhook handler accepts request bodies with permissive limits of 1MB and 30-second timeout before signature verification. An unauthenticated attacker can exhaust server connection resources by sending concurrent slow HTTP POST requests to the Feishu webhook endpoint, blocking legitimate webhook deliveries.

CVSS 4.0
6.9 MEDIUMCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/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/M
EPSS
0.33% probability · 26th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-405
Affected
openclaw/openclaw
Source
disclosure@vulncheck.com
EPSS trend
0%3%5%27 October 2026: 0.33%27 October 202627 October 2026

EPSS 0.3% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.