CVE-2026-45225

Heym before 0.0.21 contains a path traversal vulnerability in the file upload endpoint that allows authenticated users to write attacker-controlled files to arbitrary locations by supplying a crafted filename with traversal sequences. Attackers can exploit the unvalidated filename parameter in the upload_file() handler to bypass path restrictions and write, read, or delete files outside the intended storage directory.

CVSS 4.0

7.2CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:H/VA:L/SC:N/SI:N/SA:N

CVSS 3.1

7.6CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:L

EPSS

0.4% chance of exploitation in the next 30 days; higher than 28% of CVEs (scores of 2026-10-25)

CWE

CWE-22

Published

2026-05-12

Modified

2026-10-26

Record from

the NVD, synced 2026-10-26

References

• https://github.com/heymrun/heym/commit/835843e6d2bf7d018cbb8e50f28f0426eaa20c84
• https://github.com/heymrun/heym/pull/92
• https://github.com/heymrun/heym/releases/tag/v0.0.21
• https://www.vulncheck.com/advisories/heym-path-traversal-file-upload-via-upload-file
• https://github.com/heymrun/heym/pull/92

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