Server-Side Request Forgery (SSRF) in emissary - CVE-2021-32639
Published: July 2, 2021 / Updated: April 7, 2026
Vulnerability identifier: #VU125040
CSH Severity: Low
CVSSv4.0: CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:H/VI:L/VA:L/SC:L/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2021-32639
CWE-ID: CWE-918
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerable software:
emissary
emissary
Software vendor:
National Security Agency
National Security Agency
Description
The vulnerability allows a remote user to disclose sensitive information.
The vulnerability exists due to server-side request forgery in RegisterPeerAction and AddChildDirectoryAction endpoints when handling crafted POST requests. A remote privileged user can send a specially crafted request to disclose sensitive information.
Some forged requests are sent to attacker-controlled hosts, including authenticated requests to the /emissary/RegisterPeer.action endpoint and non-authenticated requests to the /emissary/Heartbeat.action endpoint.
Remediation
Install security update from vendor's website.