CVE-2026-28509: medium-severity vulnerability in langbot-app LangBot
LangBot has a Cross Site Scripting(XSS) Vulnerability
Published
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 6.3epss 0.2%
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.
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:L/A:N
Affected products
langbot-app · LangBotRelated CVEs — langbot-app LangBot
In the same product, most dangerous first.
CVE-2026-90562CRITICALLangBot before 4.10.11 Authentication Bypass via Weak Recovery KeyEPSS 0.7%CVE-2026-54449HIGHLangBot: Authenticated RCE Via MCP ConfigurationEPSS 0.7%CVE-2026-90938HIGHLangBot through 0.4.17 Unauthenticated Plugin Registration via WebSocketEPSS 0.6%CVE-2025-59835HIGHLangBot has a cross-directory file upload vulnerability, which could lead to system takeoverEPSS 0.4%CVE-2026-112265HIGHLangBot through 4.11.0 Missing Lark/Feishu Webhook Authenticity VerificationEPSS 0.2%