Vulnerability · Published Sep 2, 2026 · Assigned by VulDB

CVE-2026-84427zhayujie CowAgent Bash Tool bash.py denial of service

Medium 4.3

In plain English

A medium-severity security flaw in CowAgent from zhayujie. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 41% of all known vulnerabilities).

Severity (CVSS 3.1)4.3Medium

Exploit odds (30 days)0.5%top 59.1% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

A vulnerability was determined in zhayujie CowAgent up to 2.1.7. Affected is an unknown function of the file agent/tools/bash/bash.py of the component Bash Tool. Executing a manipulation can lead to denial of service. The attack can be launched remotely. The exploit has been publicly disclosed and may be utilized. The vendor was contacted early about this disclosure but did not respond in any way.

Affected products (as reported)

Vendor	Product	Versions
zhayujie	CowAgent	2.1.02.1.12.1.22.1.32.1.42.1.52.1.62.1.7

Weakness: CWE-404 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:P/RL:X/RC:R

References

VDB-397793 | zhayujie CowAgent Bash Tool bash.py denial of service vdb-entry
VDB-397793 | CTI Indicators (IOB, IOC, TTP, IOA) signature, permissions-required
CVE-2026-84427 | CVE Analysis and Report third-party-advisory
Submit #884137 | zhayujie CowAgent 2.1.3 Denial of Service third-party-advisory
https://github.com/outlookgp/CVE/tree/main/CowAgent_Bash_Output_Buffer_DoS_Report exploit