CVE-2026-113657: apostrophecms apostrophe · Cross-site Scripting
Affects apostrophecms apostropheSource CVE Database V5
Not known to be exploited · CVSS 3.7 Low : upgrade to 4.33.0 when convenient.
Data as of 26 Oct 2026, 13:47 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 23% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 4.33.0, 2.18.0
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:NExploitation evidence
Disclosed: evidence found.
CVE published 20 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade apostrophe to 4.33.0; sanitize-html to 2.18.0; sanitize-html to 4.33.0 or 2.18.0.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| apostrophecmsapostrophe | Affected
| Fixed in
|
| apostrophecmssanitize-html | Affected
| Fixed in
|
npmsanitize-htmlpkg:npm/sanitize-htmlOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Upgrade sanitize-html to version 2.18.0 or later, where this vulnerability is fixed. Review application configurations that permit namespace-prefixed SVG animation elements and URL-targeting attributes to ensure they do not allow unsafe URIs. Since the default sanitizer configuration is not unconditionally affected, verify if your configuration is impacted and adjust accordingly.
Description
ApostropheCMS is an open-source Node.js content management system, and sanitize-html provides a simple HTML sanitizer with a clear API. From sanitize-html 2.17.7 until 2.18.0, an application configuration that permits namespace-prefixed SVG animation elements and the relevant URL-targeting attributes can bypass the SMIL URL protection because prefixed tag names do not match the unprefixed animation-element check. The bypass can rewrite a link destination to an unsafe URI after the sanitized SVG is rendered, with script execution occurring when a user activates the affected link; the default sanitizer configuration is not unconditionally affected. This issue is fixed in sanitize-html 2.18.0.
References
- github.com/apostrophecms/apostrophe/security/advisories/GHSA-374f-7chj-9948 (opens in a new tab)
- github.com/apostrophecms/apostrophe/commit/9500b8b0e1d630d5e07fbb5fd2c25ed0943845ce (opens in a new tab)
- github.com/apostrophecms/apostrophe/commit/f84fd41cbf6c22eb8d0008fc9c25df1f7130b350 (opens in a new tab)
- github.com/apostrophecms/apostrophe/releases/tag/sanitize-html@2.18.0 (opens in a new tab)