Qualys discovers three bypasses of Ubuntu's unprivileged user namespace restrictions

Ubuntu namespace vulnerability should be addressed quickly: Expert

Linux admins who have enabled the unprivileged user namespace restriction in their recent Ubuntu environments should take action to close three new vulnerabilities that allow a threat actor to bypass the supposed protection. This warning comes after researchers at Qualys found three different ways this hardening feature can, under certain circumstances, be bypassed.  “It needs to be addressed quickly,” said Robert Beggs, CEO of Canadian incident…

The Qualys Threat Research Unit (TRU) has discovered three vulnerabilities in Ubuntu's user namespace limitations, which were reported to the Ubuntu Security team on January 15, 2025. Vulnerabilities allow attackers to gain administrative rights within user namespaces and thus make targeted use of kernel vulnerabilities. Background to user namespaces in Linux Linux allows unprivileged users to use their own namespaces with [...] The article Vuln…

Qualys discovers three bypasses of Ubuntu's unprivileged user namespace restrictions

Combined with other vulnerabilities, the flaws could lead to full system access