CVE-2022-40468: 
NixOS vulnerability analysis and mitigation

CVE-2022-40468 is a vulnerability discovered in Tinyproxy, a light-weight HTTP/HTTPS proxy daemon for POSIX operating systems. The vulnerability was disclosed on September 19, 2022, affecting Tinyproxy commit 84f203f and earlier versions. The issue involves potential leakage of left-over heap data when custom error page templates containing special non-standard variables are used (NVD, Ubuntu).

The vulnerability stems from the use of uninitialized buffers in the process_request() function. When custom error page templates are configured with special non-standard variables, the application fails to properly initialize variables used in error pages, potentially leading to information disclosure. The vulnerability has been assigned a CVSS v3.1 base score of 7.5 (High), with the vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N (Ubuntu).

The primary impact of this vulnerability is the potential disclosure of sensitive information. When exploited, the vulnerability could leak contents of the Tinyproxy server's memory through generated error pages, which might contain sensitive system information useful for attackers to launch further attacks (Gentoo).

The vulnerability has been fixed in versions after commit 84f203f. Users are advised to upgrade to the latest version of Tinyproxy. For Ubuntu users, fixes are available in version 1.11.0-1ubuntu0.1~esm1 for 22.04 LTS and corresponding versions for other releases. Gentoo users should upgrade to version 1.11.1_p20220908 or later (Gentoo, Ubuntu).