SSRF in Heymrun Heym
CVE-2026-100861
heym before 0.0.105 fails to apply egress guards to integration services that use credential-supplied base URLs, allowing authenticated users to bypass SSRF protections. Attackers can configure credentials pointing to loopback, private, or cloud-metadata addresses and read internal service responses returned as workflow node output.
Vulnerability class: SSRF (Server-Side Request Forgery)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.0 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N.
EPSS exploit prediction
EPSS: 0.002 (13.7th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 14th percentile — 13.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.000
Affected products
Weakness classification (CWE)
References
- GitHub Security Advisory (GHSA-xchj-mw74-2232) (vendor-advisory)
- VulnCheck Advisory: heym before 0.0.105 SSRF via credential-controlled base URLs (third-party-advisory)
Frequently asked questions
- What is CVE-2026-100861?
- CVE-2026-100861 is a medium-severity vulnerability in Heymrun Heym, classified under Server-Side Request Forgery (SSRF). CVSS score: 5.0/10. Published 2026-09-27.
- How severe is CVE-2026-100861?
- Medium severity. CVSS v3 base score is 5.0 out of 10.