Skip to main content
VulnerabilityPublished Updated

CVE-2026-33979: AhmedAdelFahim express-xss-sanitizer · Permissive List of Allowed Inputs

Affects AhmedAdelFahim express-xss-sanitizerSource CVE Database V5

0
Compare

Not known to be exploited · CVSS 8.2 High : upgrade to 2.0.2 soon.

Data as of 30 Oct 2026, 06:59 UTC

CVSS 3.1 base score
8.2High
How severe the flaw is on the 0–10 CVSS scale.
EPSS
0.3% chance of exploitation in 30 days – higher than 32% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch
Available – fixed in 2.0.2
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N

Exploitation evidence

  1. Disclosed: evidence found.

    CVE published 27 Mar 2026

  2. Detectable: no evidence on record.

    No public nuclei template indexed

  3. Weaponized: no evidence on record.

    No public exploit code indexed in Metasploit or Exploit-DB

  4. Exploited in the wild: no evidence on record.

    Not in CISA KEV and no source reports exploitation

  5. Observed by OffSeq 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 29 Oct 2026.

What to do

Upgrade AhmedAdelFahim express-xss-sanitizer to 2.0.2.

Affected software

ProductAffectedFixed in
AhmedAdelFahimexpress-xss-sanitizerAffected
  • <2.0.2
Fixed in
  • 2.0.2
npmexpress-xss-sanitizerpkg:npm/express-xss-sanitizerOther threatsAffected
  • <2.0.2
Fixed in
  • 2.0.2

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

Users of express-xss-sanitizer should upgrade to version 2.0.2 or later, where the sanitization logic correctly respects restrictive configurations. Patch status is not explicitly confirmed beyond the version mention, so users should consult the official project repository or vendor advisory for the latest remediation guidance.

Description

Express XSS Sanitizer is Express 4.x and 5.x middleware which sanitizes user input data (in req.body, req.query, req.headers and req.params) to prevent Cross Site Scripting (XSS) attack. A vulnerability has been identified in versions prior to 2.0.2 where restrictive sanitization configurations are silently ignored. In version 2.0.2, the validation logic has been updated to respect explicitly provided empty configurations. Now, if allowedTags or allowedAttributes are provided (even if empty), they are passed directly to sanitize-html without being overridden.

References

Community reviews

Loading reviews…