CVE-2026-97711 Serialize JavaScript: Cross-site scripting (XSS) via unescaped </script> in serialized function bodies
Attackers can execute arbitrary scripts in the victim's browser by injecting unescaped closing script tags into serialized function bodies.
- 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-2026-97711?
CVE-2026-97711 is a low-severity cross-site scripting vulnerability in yahoo serialize-javascript, published on 29 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
Serialize JavaScript serializes JavaScript values to a superset of JSON that includes regular expressions and functions. From 7.1.1 until 7.1.2, function values serialized by serialize-javascript are not fully protected against script-closing tags in attacker-influenced function source because SCRIPT_CLOSE_REGEXP can consume a second closing tag inside one match. When the serialized function is embedded in a script element, the surviving closing tag terminates the element early and causes the remaining output to be parsed as HTML, enabling cross-site scripting in the page origin. Only function values are affected; ordinary data values and options.isJSON output are unaffected. This issue is fixed in version 7.1.2.
Weakness: CWE-79
Which versions are affected by CVE-2026-97711?
2 open source packages ship an affected version, including serialize-javascript.
| Package | Affected | Fixed in |
|---|---|---|
serialize-javascript npm | From 7.1.1 | 7.1.2 |
serialize-javascript npm | From 7.1.1 | 7.1.2 |
How do I fix CVE-2026-97711?
Upgrade serialize-javascript to 7.1.2 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-2026-97711 being exploited?
There is no known exploitation of CVE-2026-97711 in the wild and no public exploit code.
Sources
Also known as CLSA-2026-1790854792, DEBIAN-CVE-2026-97711, GHSA-gfhx-hw2g-v5hg, UBUNTU-CVE-2026-97711.