CVE-2026-100865

HIGHPre-NVD 8.88.8—
EchelonGraph scoreHIGH confidence

Score 8.8 from GitHub Security Advisory (severity: HIGH) published 2026-09-27. A secondary CVSS source baseline 8.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 3 sources updated this weekElevated
8.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.3%CVSS: 8.8Exploit: Elevated riskExposed services: Not assessed

A fix is available — apply it.

Heym before 0.0.53 evaluates workflow condition expressions using Python's eval() with insufficient sandboxing in the workflow executor service. Authenticated users can edit workflow condition nodes or import malicious templates to execute arbitrary Python and OS commands as the backend process user.

CVSS v3
8.8
EG Score
8.8HIGHhigh confidence
EG Risk
56
EG Risk 56/100CISA SSVC

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity88% × 45%
Exploitation40% × 40%
Automatability0% × 15%
CISA SSVC: Track at low, Track* at medium and Attend at high mission impact.
Action: A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.
EPSS PROB
0.3%
EPSS %ILE
23rd
KEV
Not listed

CISA SSVCTrack at low, Track* at medium and Attend at high mission impact.

A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.

Exploitation public PoC (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). Mission impact is CISA's Mission & Well-being decision point, and only you can judge it: high means the affected system is essential to your organisation's mission, or its compromise could cause irreversible harm to people. CISA's decision table

Published

September 27, 2026

Last Modified

September 28, 2026

Advisory Details (2)

Auto-updated Sep 27, 2026
🔬 Proof of concept available. Patch available. Sources: github.
generic

Heym before 0.0.53 Multiple RCE and Authentication Bypass Vulnerabilities | Advisories | VulnCheck

https://www.vulncheck.com/advisories/heym-before-0.0.53-multiple-rce-and-authentication-bypass-vulnerabilities
github Patch Available🟡 PoC Available

Multiple auth/RCE vulnerabilities: workflow condition eval sandbox escape, Slack/Telegram webhook auth bypass, OAuth redirect_uri XSS, plaintext token storage · Advisory · heymrun/heym · GitHub

https://github.com/heymrun/heym/security/advisories/GHSA-pm6h-x3h5-j38h

Vendor Advisories for CVE-2026-100865(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 35× in last 7d / 38× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-10-04 08:20 UTCGHSA enrichment
  2. 2026-10-03 20:44 UTCEG score recompute
  3. 2026-10-03 20:44 UTCGHSA enrichment
  4. 2026-10-03 14:25 UTCEPSS rescore
  5. 2026-10-03 09:06 UTCGHSA enrichment
  6. 2026-10-02 21:28 UTCEG score recompute
  7. 2026-10-02 21:28 UTCGHSA enrichment
  8. 2026-10-02 09:51 UTCGHSA enrichment
  9. 2026-10-01 22:15 UTCEG score recompute
  10. 2026-10-01 22:15 UTCGHSA enrichment
  11. 2026-10-01 19:49 UTCEPSS rescore
  12. 2026-10-01 10:38 UTCGHSA enrichment
  13. 2026-09-30 22:59 UTCEG score recompute
  14. 2026-09-30 22:59 UTCGHSA enrichment
  15. 2026-09-30 15:02 UTCEPSS rescore
  16. 2026-09-30 11:23 UTCGHSA enrichment
  17. 2026-09-29 23:47 UTCEG score recompute
  18. 2026-09-29 23:47 UTCGHSA enrichment
  19. 2026-09-29 15:20 UTCEPSS rescore
  20. 2026-09-29 08:49 UTCEG score recompute
  21. 2026-09-29 08:49 UTCGHSA enrichment
  22. 2026-09-28 21:13 UTCEG score recompute
  23. 2026-09-28 21:13 UTCGHSA enrichment
  24. 2026-09-28 14:26 UTCEG score recompute
  25. 2026-09-28 14:26 UTCGHSA enrichment
Show 13 more
  1. 2026-09-28 13:57 UTCEG score recompute
  2. 2026-09-28 13:57 UTCGHSA enrichment
  3. 2026-09-28 13:50 UTCEPSS rescore
  4. 2026-09-28 05:00 UTCGHSA enrichment
  5. 2026-09-27 17:24 UTCEG score recompute
  6. 2026-09-27 17:24 UTCGHSA enrichment
  7. 2026-09-27 16:35 UTCEG score recompute
  8. 2026-09-27 16:35 UTCGHSA enrichment
  9. 2026-09-27 14:11 UTCEG score recompute
  10. 2026-09-27 14:11 UTCGHSA enrichment
  11. 2026-09-27 02:36 UTCEG score recompute
  12. 2026-09-27 01:52 UTCEG score recompute
  13. 2026-09-27 01:49 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-100865?
CVE-2026-100865 is a high vulnerability published on September 27, 2026. Heym before 0.0.53 evaluates workflow condition expressions using Python's eval() with insufficient sandboxing in the workflow executor service. Authenticated users can edit workflow condition nodes or import malicious templates to execute arbitrary Python and OS commands as the backend process…
When was CVE-2026-100865 disclosed?
CVE-2026-100865 was first published on September 27, 2026, with the most recent update on September 28, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-100865 actively exploited?
CVE-2026-100865 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.3% probability of exploitation in the next 30 days (23rd percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-100865?
CVE-2026-100865 has a CVSS base score of 8.8 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-100865?
A fix for CVE-2026-100865 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-100865 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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