Bokeh
CVE-2026-21883
MEDIUM
GHSA-793v-589g-574v
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A06:2021 - Vulnerable and Outdated Components
ASVS 5.0
V15 - Secure Coding and Architecture Hardware safety mechanism
|
| Impact | CVSS 5.4 (MEDIUM). Attack vector: Network. Complexity: Low. Privileges required: None. User interaction: Required. Public exploit/POC available. |
| Exploit ScenarioDerived | An attacker could exploit this vulnerability to compromise the affected system. |
Get an e-mail when this CVE is exploited, patched or re-scored. Free account.
Alert meAnalysisAIv1 – Mar 12, 2026
Bokeh versions 3.8.1 and below allow attackers to bypass Origin validation in WebSocket connections by registering domains that suffix-match allowlisted domains (e.g., dashboard.corp.attacker.com for allowlist entry dashboard.corp), enabling unauthorized server interaction. Public exploit code exists for this vulnerability, which could allow attackers to access sensitive data or modify visualizations on behalf of victims. The issue is resolved in Bokeh 3.8.2.
Earlier versions of this analysis (1)
Bokeh is an interactive visualization library written in Python. In versions 3.8.1 and below, if a server is configured with an allowlist (e.g., dashboard.corp), an attacker can register a domain like dashboard.corp.attacker.com (or use a subdomain if applicable) and lure a victim to visit it. [CVSS 5.4 MEDIUM]
RemediationAI
A vendor patch is available — apply it immediately. Fixed in version 3.8.2.. Restrict network access to the affected service where possible.
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 1 package in pypi
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
Affects Bokeh. Bokeh is an interactive visualization library written in Python. In versions 3.8.1 and below, if a server is configured with an allowlist (e.g., dashboard.corp), an attacker can register a domain like dashboard.corp.attacker.com (or use a subdomain if applicable) and lure a victim to visit it. The malicious site can then initiate a WebSocket connection to the vulnerable Bokeh server. Since the Origin header (e.g., http://dashboard.corp.attacker.com/) matches the allowlist according to the flawed
Know when Bokeh gets its next vulnerability
- Watch products and get an email when something new is published
- Check this CVE against your own stack and servers
- Exploit and PoC references, threat intelligence from 22 sources
No credit card · 7-day full trial
Severity by source
AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
Primary rating from GitHub Advisory.
CVSS VectorGitHub Advisory
Lifecycle Timeline
3DescriptionGitHub Advisory
Bokeh is an interactive visualization library written in Python. In versions 3.8.1 and below, if a server is configured with an allowlist (e.g., dashboard.corp), an attacker can register a domain like dashboard.corp.attacker.com (or use a subdomain if applicable) and lure a victim to visit it. The malicious site can then initiate a WebSocket connection to the vulnerable Bokeh server. Since the Origin header (e.g., http://dashboard.corp.attacker.com/) matches the allowlist according to the flawed logic, the connection is accepted. Once connected, the attacker can interact with the Bokeh server on behalf of the victim, potentially accessing sensitive data, or modifying visualizations. This issue is fixed in version 3.8.2.
Blast Radius
ecosystem impact- 15 pypi packages depend on bokeh (10 direct, 5 indirect)
Ecosystem-wide dependent count for version 3.8.2.
Executive ViewAI
Organizations using Python. In should be aware of moderate risk from CVE-2026-21883 rated CVSS 5.4. Exploitation could compromise the security of affected deployments. Proof-of-concept code is publicly available. A patch is available and should be applied during regular vulnerability management.
Apply vendor patch. If patching is delayed: restrict network access and enable monitoring.
Threat Intelligence Overview
NVD
CVE.org
EPSS
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
Exploit-DB