All vulnerabilities
CVE-2026-101049GHSA-pm6h-x3h5-j38h

Heym before 0.0.53 Slack Webhook Signature Verification Bypass

heymrun heym
Open in ThreatlineRecord JSON
CVSS
8.3High
ExploitationPublic exploit codeCISA's assessment says proof of concept code is public, assessed 28 Sep 2026. Not in the KEV catalogCISA via CVE List
Exploit odds (EPSS)0.30%Chance of exploitation activity in the next 30 days, higher than 21% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed in0.0.53Fixed versionCVE List
Published27 Sep 2026Updated 28 Sep 2026CVE List

What fixes it

A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.

Description

Heym before 0.0.53 fails to verify Slack request signatures when trigger nodes lack credential IDs or have empty signing secrets. Remote unauthenticated attackers can send forged Slack events to known webhook URLs to trigger workflows with the owner's credentials.

Text from CVE List

Affected versions 2

  • heymaffected: all versions before 0.0.53CVE List
  • heymunaffected: 0.0.53CVE List

References 3