CVE-2021-33477: rxvt-unicode 9.22, rxvt 2.7.10, mrxvt 0.5.4, and Eterm 0.9.7 allow (potentially remote) code execution beca...

Security readout for executives and security teams

Certain older terminal emulators can mis-handle a specific escape sequence and treat terminal output as executable behavior. The business risk is highest for systems where users view untrusted text in these terminals. Sources indicate vendor and distribution updates were issued, but the bundle does not provide CVSS scoring. Exposure is most likely on Unix/Linux workstations or servers using the listed terminal emulators, especially where untrusted terminal output is viewed. General web applications are not directly implicated by the provided sources. Treat this as a focused high-priority remediation for Linux or Unix estates using these terminal emulators, not a broad enterprise emergency. Prioritize privileged users and legacy systems first. Mitigation focus: Inventory rxvt-unicode, rxvt, mrxvt, and Eterm installations and versions.; Apply vendor or distribution security updates for affected packages.; Remove unused affected terminal emulators from managed systems..

Prepared

Jun 3, 2026, 02:27 UTC (UTC+00:00)

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.