CVE Vulnerabilities

CVE-2023-26046

Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS)

Published: Mar 02, 2023 | Modified: Nov 21, 2024
CVSS 3.x
6.1
MEDIUM
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
CVSS 2.x
RedHat/V2
RedHat/V3
Ubuntu

teler-waf is a Go HTTP middleware that provides teler IDS functionality to protect against web-based attacks. In teler-waf prior to version 0.1.1 is vulnerable to bypassing common web attack rules when a specific HTML entities payload is used. This vulnerability allows an attacker to execute arbitrary JavaScript code on the victims browser and compromise the security of the web application. The vulnerability exists due to teler-waf failure to properly sanitize and filter HTML entities in user input. An attacker can exploit this vulnerability to bypass common web attack threat rules in teler-waf and launch cross-site scripting (XSS) attacks. The attacker can execute arbitrary JavaScript code on the victims browser and steal sensitive information, such as login credentials and session tokens, or take control of the victims browser and perform malicious actions. This issue has been fixed in version 0.1.1.

Weakness

The product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes special characters such as “<”, “>”, and “&” that could be interpreted as web-scripting elements when they are sent to a downstream component that processes web pages.

Affected Software

Name Vendor Start Version End Version
Teler-waf Kitabisa * 0.1.1 (excluding)

Potential Mitigations

  • Use and specify an output encoding that can be handled by the downstream component that is reading the output. Common encodings include ISO-8859-1, UTF-7, and UTF-8. When an encoding is not specified, a downstream component may choose a different encoding, either by assuming a default encoding or automatically inferring which encoding is being used, which can be erroneous. When the encodings are inconsistent, the downstream component might treat some character or byte sequences as special, even if they are not special in the original encoding. Attackers might then be able to exploit this discrepancy and conduct injection attacks; they even might be able to bypass protection mechanisms that assume the original encoding is also being used by the downstream component.
  • The problem of inconsistent output encodings often arises in web pages. If an encoding is not specified in an HTTP header, web browsers often guess about which encoding is being used. This can open up the browser to subtle XSS attacks.

References