CVE-2026-82654 SiYuan before v3.8.1 Stored XSS via block name
Attackers can inject malicious scripts via block names that execute when other users view related documents in SiYuan.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-82654?
CVE-2026-82654 is a critical cross-site scripting vulnerability in siyuan-note siyuan, published on 30 Aug 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official description
SiYuan before v3.8.1 fails to properly escape block name, alias, and memo fields in hint, backlink, and breadcrumb rendering functions. Attackers can set a block's name to contain HTML/script tags that execute when another user views documents referencing or displaying that block.
Weakness: CWE-79
Which versions are affected by CVE-2026-82654?
How do I fix CVE-2026-82654?
No fix has been published for CVE-2026-82654 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-2026-82654 being exploited?
There is no known exploitation of CVE-2026-82654 in the wild and no public exploit code.
Sources
Also known as GHSA-5x6r-p3h7-38vj, GHSA-hf87-qh3j-3p88.