CVE-2021-26953: 
Rust vulnerability analysis and mitigation

An issue was discovered in the postscript crate before 0.14.0 for Rust. The vulnerability (CVE-2021-26953) involves passing an uninitialized buffer to a user-provided Read implementation, which might allow attackers to obtain sensitive information from uninitialized memory locations. The vulnerability was discovered and reported on January 30, 2021, and the advisory was issued on January 31, 2021 (RustSec Advisory).

The vulnerability occurs when the postscript crate passes an uninitialized buffer to a user-provided Read implementation. Arbitrary Read implementations can read from the uninitialized buffer, leading to memory exposure, and can also return an incorrect number of bytes written to the buffer. Reading from uninitialized memory produces undefined values that can quickly invoke undefined behavior. The vulnerability has been assigned a CVSS v3.1 base score of 7.5 (HIGH) with vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N (RustSec Advisory).

The vulnerability can lead to exposure of sensitive information from uninitialized memory locations. This could potentially allow attackers to access confidential data that was previously stored in memory. The CVSS score indicates high confidentiality impact, while integrity and availability remain unaffected (RustSec Advisory).

The vulnerability is exploitable through network vectors with low attack complexity and requires no privileges or user interaction. The scope is unchanged, meaning the impact is limited to the vulnerable component's security scope (RustSec Advisory).

The vulnerability was fixed in version 0.14.0 of the postscript crate by zero-initializing the buffer before handing it to a user-provided Read implementation. The fix was implemented in commit 8026286. Users are advised to upgrade to version 0.14.0 or later (RustSec Advisory).