Vulnerability · Published Sep 28, 2026 · Assigned by VulDB

CVE-2026-101100ag-ui-protocol ag-ui Middleware filter-tool-calls.ts FilterToolCallsMiddleware cleanup

Medium 5.4

In plain English

A medium-severity security flaw in ag-ui from ag-ui-protocol. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 23% of all known vulnerabilities).

Severity (CVSS 3.1)5.4Medium

Exploit odds (30 days)0.3%top 77.3% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

A flaw has been found in ag-ui-protocol ag-ui up to 2026-09-07. This vulnerability affects the function FilterToolCallsMiddleware of the file sdks/typescript/packages/client/src/middleware/filter-tool-calls.ts of the component Middleware. Executing a manipulation can lead to incomplete cleanup. The attack may be launched remotely. Upgrading to version 2026-09-08 is able to resolve this issue. This patch is called c346119fe870b70f5c19738ee5119f3e1456e59d. It is suggested to upgrade the affected component.

Affected products (as reported)

Vendor	Product	Versions
ag-ui-protocol	ag-ui	2026-09-07

Weakness: CWE-459 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L/E:X/RL:O/RC:C

References

VDB-410975 | ag-ui-protocol ag-ui Middleware filter-tool-calls.ts FilterToolCallsMiddleware cleanup vdb-entry, technical-description
VDB-410975 | CTI Indicators (IOB, IOC, IOA) signature, permissions-required
CVE-2026-101100 | CVE Analysis and Report third-party-advisory
Submit #934980 | ag-ui-protocol ag-ui v1.0 CWE-459 third-party-advisory
https://github.com/ag-ui-protocol/ag-ui/issues/2443 issue-tracking
https://github.com/ag-ui-protocol/ag-ui/pull/2494 issue-tracking, patch
https://github.com/ag-ui-protocol/ag-ui/commit/c346119fe870b70f5c19738ee5119f3e1456e59d patch
https://github.com/ag-ui-protocol/ag-ui/releases/tag/release/2026-09-08 patch
https://github.com/ag-ui-protocol/ag-ui/ product