What is CVE-2026-117503?

CVE-2026-117503 is a medium-severity vulnerability in A2aproject A2a-Go, classified under Uncontrolled Resource Consumption. CVSS score: 5.3/10. Published 2026-10-27.

How severe is CVE-2026-117503?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Resource exhaustion in A2aproject A2a-Go

CVE-2026-117503

A vulnerability was determined in a2aproject a2a-go up to 2.4.0. Impacted is an unknown function of the file a2asrv/rest.go of the component REST SSE handler. This manipulation causes resource consumption. It is possible to initiate the attack remotely. Upgrading to version 2.5.0 is recommended to address this issue. Patch name: ff6035bd21e44bb3ee1bfa547885b8c08327fa01. It is recommended to upgrade the affected component.

Vulnerability class: DoS (Denial of Service)

Published 2026-10-27 · last modified 2026-10-27.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

A2aproject A2a-Go — versions 2.0, 2.1, 2.2

Weakness classification (CWE)

References

vuldb.com/vuln/427070 (vdb-entry)
vuldb.com/vuln/427070/cti (signature, permissions-required)
vuldb.com/cve/CVE-2026-117503 (third-party-advisory)
vuldb.com/submit/1015052 (third-party-advisory)
github.com/a2aproject/a2a-go/pull/396 (issue-tracking, patch)
github.com/a2aproject/a2a-go/commit/ff6035bd21e44bb3ee1bfa547885b8c08327fa01 (patch)
github.com/a2aproject/a2a-go/releases/tag/v2.5.0 (patch)
github.com/a2aproject/a2a-go/ (product)

Frequently asked questions

What is CVE-2026-117503?: CVE-2026-117503 is a medium-severity vulnerability in A2aproject A2a-Go, classified under Uncontrolled Resource Consumption. CVSS score: 5.3/10. Published 2026-10-27.
How severe is CVE-2026-117503?: Medium severity. CVSS v3 base score is 5.3 out of 10.