CVE-2026-27901 Svelte vulnerable to XSS during SSR with contenteditable `bind:innerText` and `bind:textContent`
Attackers can inject malicious scripts via unescaped contenteditable bindings during server-side rendering in Svelte applications.
- 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
- Available
What is CVE-2026-27901?
CVE-2026-27901 is a medium-severity cross-site scripting vulnerability in sveltejs svelte, published on 26 Feb 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
Svelte performance oriented web framework. Prior to version 5.53.5, the contents of `bind:innerText` and `bind:textContent` on `contenteditable` elements were not properly escaped. This could enable HTML injection and Cross-Site Scripting (XSS) if rendering untrusted data as the binding's initial value on the server. Version 5.53.5 fixes the issue.
Weakness: CWE-79
Which versions are affected by CVE-2026-27901?
2 open source packages ship an affected version, including svelte. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
svelte npm | All versions | 5.53.5 |
svelte npm | All versions | 5.53.5 |
Products include Svelte Svelte.
How do I fix CVE-2026-27901?
Upgrade svelte to 5.53.5 or later.
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-2026-27901 being exploited?
There is no known exploitation of CVE-2026-27901 in the wild and no public exploit code.
Other vulnerabilities in sveltejs svelte
- CVE-2021-29261 Code injection in n/a
- CVE-2026-42567 Svelte: ReDoS in `<svelte:element>` Tag Validation
- CVE-2024-45047 Potential mXSS vulnerability due to improper HTML escaping in svelte
- CVE-2022-25875 Cross-site Scripting (XSS)
- CVE-2026-42573 Svelte: XSS via DOM Clobbering of Internal Framework State
Sources
Also known as GHSA-phwv-c562-gvmh.