CVE-2026-40516
OpenHarness SSRF via web_fetch and web_search
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
OpenHarness SSRF via web_fetch and web_search
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.
- Record
CVE-2026-40516- CVSS 4.0
- 7.8 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:H/SI:L/SA:L - CVSS 3.1
- 8.3 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:L - Weakness
- CWE-918
- Updated
- 2026-11-02
EUVDEUVD-2026-23452
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.
- Record
EUVD-2026-23452- CVSS 4.0
- 7.8 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:H/SI:L/SA:L - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-785m-9q28-jp3m
OpenHarness before commit bd4df81 contains a server-side request forgery vulnerability in the...
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.
- Record
GHSA-785m-9q28-jp3m- CVSS 4.0
- 7.8 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:H/SI:L/SA:L/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 - CVSS 3.1
- 8.3 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:L - Weakness
- CWE-918
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2026-40516- CVSS 4.0
- 7.8 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:H/SI:L/SA:L/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 - CVSS 3.1
- 8.3 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:L - CVSS 3.1
- 6.3 Medium
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:N/A:N - Weakness
- CWE-918
- Updated
- 2026-11-02
OSV
OpenHarness SSRF via web_fetch and web_search
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.
- Record
CVE-2026-40516- CVSS 4.0
- 7.8 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:H/SI:L/SA:L - Weakness
- CWE-918
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-40516 is a high vulnerability (CVSS 7.8) in Hkuds Openharness, published April 17, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.18%, the 7th percentile. No source names a fixed version.
References
github.com/HKUDS/OpenHarness/pull/92
vulncheck.com/advisories/openharness-ssrf-via-web-fetch-and-web-search
nvd.nist.gov/vuln/detail/CVE-2026-40516