CVE-2021-41259 Information

Description

Nim is a systems programming language with a focus on efficiency expressiveness and elegance. In affected versions the uri.parseUri function which may be used to validate URIs accepts null bytes in the input URI. This behavior could be used to bypass URI validation. For example: parseUri(\http://localhost\0hello).hostname is set to \localhost\0hello. Additionally httpclient.getContent accepts null bytes in the input URL and ignores any data after the first null byte. Example: getContent(\http://localhost\0hello) makes a request to localhost:80. An attacker can use a null bytes to bypass the check and mount a SSRF attack.

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Reference

https://github.com/nim-lang/security/security/advisories/GHSA-3gg2-rw3q-qwgc

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

HIGH

Availability Impact

HIGH

Base Score

HIGH

Base Severity

9.8