Predictive Vulnerability Intelligence.

Product

  • Product
  • Pricing
  • Documentation

Company

  • About
  • Partnerships
  • Blog
  • Support

Legal

  • Terms
  • Privacy
  • Data Licensing

© 2026 FAUCET Technologies LLC. All rights reserved.

CVE-2021-21422

21
FAUCET Score

CVE-2021-21422 is a cross-site scripting (XSS) vulnerability affecting mongo-express, a web-based MongoDB admin interface. It allows an attacker to inject malicious JavaScript into data cells, which can then be executed when an administrator views the unsanitized content. This could lead to data exfiltration or other unauthorized actions. Rated as Medium severity (CVSS 6.1), the vulnerability requires user interaction (UI:R) and has low impact on confidentiality and integrity (C:L, I:L). The attack vector is network-based (AV:N) with low attack complexity (AC:L). Currently, there is no evidence of active exploitation, nor are there publicly available exploit modules or significant community discussion surrounding this CVE. It is not listed in the CISA KEV catalog.

Impacted Technologies

VendorProductVersion(s)CPE
<= 0.54.0CPE matchmatch criteria
cpe:2.3:a:mongo-express_project:mongo-express:*:*:*:*:*:node.js:*:*
1.0.0CPE matchmatch criteria
cpe:2.3:a:mongo-express_project:mongo-express:1.0.0:alpha1:*:*:*:*:*:*
1.0.0CPE matchmatch criteria
cpe:2.3:a:mongo-express_project:mongo-express:1.0.0:alpha3:*:*:*:*:*:*

CVSS Data

CVSS version used by this source: 3.1

8.1HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N

Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
NONE
Exploitability Score
2.8
Impact Score
5.2
CvssVersion
3.1

Exploit Intelligence

EPSS Score
1.57%
Probability of exploitation in next 30 days
EPSS Percentile
72.8%
Percentile rank of EPSS score among Peer Group
As of 2026-07-27
Model: v2026.06.15
This CVE's current EPSS score of 0.0157 is in the 85th percentile among its peer group of 26,234 CVEs.

Social Chatter

The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.1 Bluesky, 0.0 Mastodon, and 0.1 GitHub mentions.

Media Mentions

No media coverage found for this CVE.

The average CVE in this peer group has 0.1 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.

Remediation

Patch Available

Vendor Patches (2)

github_advisorypatch availablevia nvd_reference
View patch
npmpatch availablevia ghsa
Product: mongo-expressFixed in: 1.0.0-alpha.4

Vendor Advisories (1)

npmGHSA-7p8h-86p5-wv3phigh

Cross-site scripting

Jun 28, 2021

References

github.com / mongo-express/mongo-express/commit/f5e0d4931f856f032f22664b5e5901d5950cfd4b
PatchThird Party Advisory
github.com / mongo-express/mongo-express/issues/577
ExploitThird Party Advisory
github.com / mongo-express/mongo-express/security/advisories/GHSA-7p8h-86p5-wv3p
ExploitThird Party Advisory