Medium severity · published Oct 5, 2026
CVE-2026-105396
Heym before v0.0.112 HITL Review Token Leak via Spoofable Origin Header
5.4
CVSS
0.1%
EPSS
No
On KEV
Description
Heym before v0.0.112 contains a token leakage vulnerability in build_public_base_url() that allows unauthenticated attackers to redirect HITL review links by spoofing Origin or X-Forwarded-Host headers. Attackers can trigger anonymous workflows with forged headers so reviewer notifications point to attacker domains, capturing capability tokens to submit decisions executed with owner credentials.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.1% · higher than 1% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
HE
heym · heymrun
before 0.0.112 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-105396
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-105396
vendor-advisory
https://github.com/heymrun/heym/security/advisories/GHSA-6rv3-wh25-7pg5
third-party-advisory
https://www.vulncheck.com/advisories/heym-before-0.0.112-hitl-review-token-leak-via-spoofable-origin-header
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