CVE-2026-87812 SiYuan before v3.8.2 Stored XSS via Bazaar iconURL
Attackers can inject malicious JavaScript via Bazaar package icons, allowing code execution and state manipulation in SiYuan.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-87812?
CVE-2026-87812 is a high-severity cross-site scripting vulnerability in siyuan-note siyuan, published on 9 Sep 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
SiYuan before v3.8.2 contains a stored cross-site scripting vulnerability in Bazaar package cards where the iconURL metadata is inserted directly into HTML img src attributes without escaping. Attackers can inject malicious URLs with event handlers that execute JavaScript in the authenticated SiYuan origin when users view Bazaar listings, enabling API requests and application state manipulation.
Weakness: CWE-79
Which versions are affected by CVE-2026-87812?
How do I fix CVE-2026-87812?
No fix has been published for CVE-2026-87812 yet. Limit exposure of the affected software until one is available.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2026-87812 being exploited?
There is no known exploitation of CVE-2026-87812 in the wild and no public exploit code.
Sources
Also known as GHSA-rv6c-xvcj-4qwg, GHSA-rvcf-q4h8-w6c9.