6.9
MEDIUM CVSS 4.0
CVE-2026-117503
a2aproject a2a-go REST SSE handler rest.go resource consumption
Description

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.

INFO

Published Date :

Oct. 27, 2026, 2:16 p.m.

Last Modified :

Oct. 27, 2026, 2:52 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-117503 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 A2aproject a2a-go
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 2.0 MEDIUM [email protected]
CVSS 3.1 MEDIUM [email protected]
CVSS 4.0 MEDIUM [email protected]
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-117503 is associated with the following CWEs:

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-117503 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-117503 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Oct. 27, 2026

    Action Type Old Value New Value
    Added Description 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.
    Added CVSS V4.0 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/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
    Added CVSS V2 (AV:N/AC:L/Au:N/C:N/I:N/A:P)
    Added CWE CWE-404
    Added CWE CWE-400
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/117xxx/CVE-2026-117503.json">CVE-2026-117503</a>
    Added Reference https://github.com/a2aproject/a2a-go/
    Added Reference https://github.com/a2aproject/a2a-go/commit/ff6035bd21e44bb3ee1bfa547885b8c08327fa01
    Added Reference https://github.com/a2aproject/a2a-go/pull/396
    Added Reference https://github.com/a2aproject/a2a-go/releases/tag/v2.5.0
    Added Reference https://vuldb.com/cve/CVE-2026-117503
    Added Reference https://vuldb.com/submit/1015052
    Added Reference https://vuldb.com/vuln/427070
    Added Reference https://vuldb.com/vuln/427070/cti
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.