What’s Vulnerable › Vulnerabilities

CVE-2026-40516: OpenHarness SSRF via web_fetch and web_search

• Severity: medium (CVSS 6.3 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2026-04-17 · updated 2026-10-26
• Weakness: CWE-918

Description

OpenHarness before commit bd4df81 contains a server-side request forgery vulnerability in the web_fetch and web_search tools that allows attackers to access private and localhost HTTP services by manipulating tool parameters without proper validation of target addresses. Attackers can influence an agent session to invoke these tools against loopback, RFC1918, link-local, or other non-public addresses to read response bodies from local development services, cloud metadata endpoints, admin panels, or other private HTTP services reachable from the victim host.

Affected products

• HKUDS OpenHarness: before 2026-04-11 — fixed in 2026-04-11

How to fix

Upgrade to a fixed version: HKUDS OpenHarness 2026-04-11. Check the vendor advisory for mitigations.

References

• https://github.com/HKUDS/OpenHarness/commit/bd4df81f634f8c7cddcc3fdf7f561a13dcbf03ae
• https://github.com/HKUDS/OpenHarness/pull/92
• https://www.vulncheck.com/advisories/openharness-ssrf-via-web-fetch-and-web-search
• https://github.com/HKUDS/OpenHarness/pull/92

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