CVE-2026-84207 json
Heym before 0.0.98 SSRF via WebSocket endpoints
published 2mo ago modified 2mo ago also EUVD-2026-69295 , GHSA-mqw6-g845-w596
Unreviewed: the maintainers' own advisory
Published by the maintainers on their GitHub repository heymrun/heym. GitHub has not reviewed it into the GitHub Advisory Database, so the affected packages and versions are the maintainers' word. Read the full advisory on GitHub.
- cvss
- 5.4
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 28%
- public exploits
- 0
- none known
Summary
Heym before 0.0.98 fails to apply SSRF egress guards to WebSocket Send and WebSocket Trigger nodes, allowing authenticated users to connect to internal services. Attackers can craft workflow nodes with arbitrary URLs and headers to reach internal services and read responses from the WebSocket Trigger node.
Patch / fix
- heymrun heym 0.0.98
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- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- partial
- Assessed
- 2mo ago
Exploit prediction
0.35% chance of exploitation in the next 30 days, higher than 28% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 5.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N |
| CNA | 3.1 | 5.4 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N |
| CNA | 4.0 | 5.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Affected products
- heymrun heym
Classification
- Weakness
-
- CWE-918 Server-Side Request Forgery
References
-
github.com
/heymrun/heym/commit/540aade7c7495295062f32f4dfd0d6805f066f0c
patch
-
github.com
/heymrun/heym/security/advisories/GHSA-mqw6-g845-w596
vendor-advisory, advisory
-
github.com
/heymrun/heym
product
-
github.com
/heymrun/heym/releases/tag/v0.0.98
release-notes
-
github.com
/heymrun/heym/blob/v0.0.97/backend/app/services/websocket_utils.py
technical-description
-
github.com
/heymrun/heym/blob/v0.0.97/backend/app/services/websocket_trigger_service.py
technical-description
-
vulncheck.com
/advisories/heym-before-0.0.98-ssrf-via-websocket-endpoints
third-party-advisory
Sources
- CVE List CVE-2026-84207
- NVD CVE-2026-84207
- Maintainer advisory GHSA-mqw6-g845-w596
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
The maintainers of heymrun/heym published their own advisory on GitHub. Reviewed sources take precedence over it.