What is CVE-2023-1720?

CVE-2023-1720 is a critical-severity vulnerability in Bitrix24, classified under Unrestricted Upload of File with Dangerous Type. CVSS score: 9.6/10. Published 2023-11-01.

How severe is CVE-2023-1720?

Critical severity. CVSS v3 base score is 9.6 out of 10.

Is CVE-2023-1720 known to be exploited?

2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Arbitrary file upload in Bitrix24

CVE-2023-1720

Lack of mime type response header in Bitrix24 22.0.300 allows authenticated remote attackers to execute arbitrary JavaScript code in the victim's browser, and possibly execute arbitrary PHP code on the server if the victim has administrator privilege, via uploading a crafted HTML file through /desktop_app/file.ajax.php?action=uploadfile.

Vulnerability class: Unrestricted File Upload

EPSS: 0.009 (54.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.6 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H.

Affected products

Bitrix24 — versions 22.0.300, 0

Weakness classification (CWE)

CWE-434 — Unrestricted Upload of File with Dangerous Type

Public proof-of-concept exploits

References

info@starlabs.sg (Exploit, Third Party Advisory, third-party-advisory)

Frequently asked questions

What is CVE-2023-1720?: CVE-2023-1720 is a critical-severity vulnerability in Bitrix24, classified under Unrestricted Upload of File with Dangerous Type. CVSS score: 9.6/10. Published 2023-11-01.
How severe is CVE-2023-1720?: Critical severity. CVSS v3 base score is 9.6 out of 10.
Is CVE-2023-1720 known to be exploited?: 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.