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-2026-28509

19
FAUCET Score

CVE-2026-28509 is a cross-site scripting (XSS) vulnerability in LangBot, a global IM bot platform for LLMs, affecting versions prior to 4.8.7. The flaw arises from the web UI's use of rehypeRaw to render user-supplied raw HTML, allowing for malicious script injection. With a CVSS score of 6.3 (MEDIUM), successful exploitation requires user interaction and authenticated access, potentially leading to high confidentiality impact and low integrity impact. There is currently no evidence of active exploitation, public exploit code (Metasploit, Nuclei, ExploitDB), or significant community discussion or media coverage surrounding this vulnerability.

Impacted Technologies

VendorProductVersion(s)CPE
< 4.8.7CPE matchmatch criteria
cpe:2.3:a:langbot:langbot:*:*:*:*:*:*:*:*

CVSS Data

CVSS version used by this source: 3.1

6.3MEDIUM

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

Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
LOW
Availability Impact
NONE
Exploitability Score
2.1
Impact Score
4.2
CvssVersion
3.1

Exploit Intelligence

EPSS Score
0.19%
Probability of exploitation in next 30 days
EPSS Percentile
8.6%
Percentile rank of EPSS score among Peer Group
As of 2026-07-26
Model: v2026.06.15
This CVE's current EPSS score of 0.0019 is in the 7th percentile among its peer group of 15,224 CVEs.

Social Chatter

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

Remediation

Remediation records are not available for this CVE.

References

github.com / langbot-app/LangBot/commit/614621ab7b84fe50da3c6137705cde5a99429866
Patch
github.com / langbot-app/LangBot/security/advisories/GHSA-w8gq-g4pc-xh3h
ExploitVendor Advisory