Log in Start free

Vulnerability · Published Apr 5, 2026 · Assigned by VulDB

CVE-2026-5538QingdaoU OnlineJudge judge_server_heartbeat Endpoint JudgeServer.service_url server-side request forgery

Medium 6.3

In plain English

A medium-severity server-side request forgery in OnlineJudge from QingdaoU. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 11% of all known vulnerabilities).

Severity (CVSS 3.1)6.3Medium
Exploit odds (30 days)0.2%top 88.8% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known

Official description

A vulnerability was detected in QingdaoU OnlineJudge up to 1.6.1. Affected by this issue is the function service_url of the file JudgeServer.service_url of the component judge_server_heartbeat Endpoint. The manipulation results in server-side request forgery. It is possible to launch the attack remotely. The vendor was contacted early about this disclosure but did not respond in any way.

Affected products (as reported)

VendorProductVersions
QingdaoU OnlineJudge 1.6.01.6.1

Weakness: CWE-918 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L/E:X/RL:X/RC:R

References