CVE-2026-1731

CVE-2026-1731 is a critical pre-authentication remote code execution vulnerability affecting BeyondTrust Remote Support (RS) and certain older versions of Privileged Remote Access (PRA). Classified under CWE-78 (OS Command Injection), it carries a CVSS v3.1 base score of 9.8 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H). The flaw enables an unauthenticated remote attacker to execute operating system commands in the context of the site user by sending specially crafted requests.

An unauthenticated attacker with network access can exploit this vulnerability without privileges or user interaction. Successful exploitation grants high-impact confidentiality, integrity, and availability effects, allowing arbitrary OS command execution as the site user, potentially leading to full system compromise on affected BeyondTrust installations.

BeyondTrust has published security advisories detailing the issue, including KB0023293 and BT26-02, which likely outline affected versions and patching instructions. A proof-of-concept is available on GitHub, and reconnaissance activity has been observed as noted by GreyNoise.

This vulnerability appears in the CISA Known Exploited Vulnerabilities Catalog, indicating active real-world exploitation. Security practitioners should prioritize patching and monitor for related indicators.