Stored XSS via unsafe markdown rendering
Published May 13, 2020 · Updated Sep 16, 2024
XSS in Open Build Service before 7cc32c8e2ff7290698e101d9a80a9dc29a5500fb lets remote attackers run JavaScript via stored markdown. OBSApi::MarkdownRenderer used Redcarpet's HTML renderer, which emitted attacker-controlled markdown HTML without safe filtering; the fix switches to Redcarpet::Render::Safe. The attack requires access to submit persistent markdown and a victim viewing the rendered content, allowing script execution in that viewer's security context with confidentiality and integrity impact.
Summary
What happened
XSS in Open Build Service before 7cc32c8e2ff7290698e101d9a80a9dc29a5500fb lets remote attackers run JavaScript via stored markdown. OBSApi::MarkdownRenderer used Redcarpet's HTML renderer, which emitted attacker-controlled markdown HTML without safe filtering; the fix switches to Redcarpet::Render::Safe. The attack requires access to submit persistent markdown and a victim viewing the rendered content, allowing script execution in that viewer's security context with confidentiality and integrity impact.
The record
- CVE
- CVE-2020-8020
- Published
- May 13, 2020
- Updated
- Sep 16, 2024
- Vendor
- OpenSUSE
- Product
- Open Build Service
- Classifications
- CWE-79, T1189
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- May 13, 2020CVE publishedPublication date reported by the CVE source.
- Sep 16, 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?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=open-build-service <7cc32c8e2ff7290698e101d9a80a9dc29a5500fb
What conditions does exploitation require?
What is affected?
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
No public exploit references are available in this record.
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