Cross-site scripting via null-byte filter mismatch
Published Jun 1, 2020 · Updated Aug 4, 2024
Cross-site scripting in the Bitrix24 Web Application Firewall through 20.0.950 allows remote attackers to execute script in a victim's browser. The addVariable method removes null bytes from request parameters, while isDangerBody compares the altered values with the original script body and misses the match. Exploitation requires attacker-controlled input reflected inside an executable script block and a victim who loads the crafted request.
Summary
What happened
Cross-site scripting in the Bitrix24 Web Application Firewall through 20.0.950 allows remote attackers to execute script in a victim's browser. The addVariable method removes null bytes from request parameters, while isDangerBody compares the altered values with the original script body and misses the match. Exploitation requires attacker-controlled input reflected inside an executable script block and a victim who loads the crafted request.
The record
- CVE
- CVE-2020-13758
- Published
- Jun 1, 2020
- Updated
- Aug 4, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-79, T1189
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jun 1, 2020CVE publishedPublication date reported by the CVE source.
- Aug 4, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
What conditions does exploitation require?
What is affected?
Affected products and versions are unavailable in this record.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- Bitrix WAF null-byte bypass proof of conceptproof of concept · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo