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PatchSiren cyber security CVE debrief

CVE-2026-45225 heymrun CVE debrief

CVE-2026-45225 is a path traversal vulnerability in the file upload endpoint of Heym before version 0.0.21. This vulnerability allows authenticated users to write attacker-controlled files to arbitrary locations by supplying a crafted filename with traversal sequences. The unvalidated filename parameter in the upload_file() handler can be exploited to bypass path restrictions and write, read, or delete files outside the intended storage directory. Affected product deployments should be reviewed for exposure.

Vendor
heymrun
Product
heym
CVSS
HIGH 7.2
CISA KEV
Not listed in stored evidence
Original CVE published
2026-05-12
Original CVE updated
2026-07-14
Advisory published
2026-05-12
Advisory updated
2026-07-14

Who should care

Users of Heym before version 0.0.21 should be aware of this vulnerability and take immediate action to update to a patched version. Authenticated users of the affected versions are at risk of being exploited. Operators, platform administrators, vulnerability management teams, and security teams should review the vulnerability and implement necessary mitigations.

Technical summary

The vulnerability exists in the file upload endpoint of Heym, where the filename parameter is not properly validated. This allows an attacker to supply a filename with traversal sequences, potentially leading to writing, reading, or deleting files outside the intended directory. The CVSS score for this vulnerability is 7.2, indicating a high severity. Affected product context suggests that authenticated users can exploit this vulnerability.

Defensive priority

High

Recommended defensive actions

  • Update Heym to version 0.0.21 or later
  • Restrict access to the file upload endpoint
  • Monitor for suspicious file upload activity
  • Implement additional security measures such as file upload validation and sanitization
  • Review compensating controls for exposed systems while remediation is scheduled and verified
  • Check relevant monitoring, detection, and logs for exposed assets that need extra review
  • Track exceptions, retest remediated assets, and close the item only after evidence is documented

Evidence notes

The CVE record was published on 2026-05-12T22:16:37.990Z and last modified on 2026-07-14T21:16:55.190Z. The NVD entry is currently Deferred. Evidence is limited to CVE and NVD information. Defenders should verify affected product deployments and review official advisories.

Official resources

AI-assisted PatchSiren debrief based on the supplied source corpus. The CVE record was published on 2026-05-12T22:16:37.990Z and has not been modified since then. The NVD entry is currently Deferred.