PatchTheCVECVE-2026-28509: LangBot is a global IM bot platform designed for LLMs
CVE-2026-28509 is a medium-severity flaw (CVSS 6.3) affecting langbot. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
LangBot is a global IM bot platform designed for LLMs. Prior to version 4.8.7, LangBot’s web UI renders user-supplied raw HTML using rehypeRaw, which can lead to a cross-site scripting (XSS) vulnerability. This issue has been patched in version 4.8.7.
Why this priority
- Public exploit reference
A fixed release or distro patch exists.
Risk facts
| CVSS score | 6.3 (Medium) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | Low |
| User interaction | Required |
| EPSS exploit chance | 0.2% (top 90%) |
| CISA exploited list | No |
| Weakness | CWE-79 |
| Published | 2026-03-06 |
| Last modified | 2026-06-17 |
Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2026-28509?
langbot: upgrade to 4.8.7. Exact commands for each OS are on this page.
Is CVE-2026-28509 being exploited?
CVE-2026-28509 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2026-28509 affect?
CVE-2026-28509 affects langbot. Severity is medium (CVSS 6.3). LangBot is a global IM bot platform designed for LLMs. Prior to version 4.8.7, LangBot’s web UI renders user-supplied raw HTML using rehypeRaw, which can lead to a cross-site scripting (XSS) vulnerability. This issue has been patched in ver
How urgent is CVE-2026-28509?
Priority 29/100. Public exploit reference