CVE-2021-42840
CWE-434Published: October 22, 2021· Updated: Jun 17, 2026
Official Description
SuiteCRM before 7.11.19 allows remote code execution via the system settings Log File Name setting. In certain circumstances involving admin account takeover, logger_file_name can refer to an attacker-controlled PHP file under the web root, because only the all-lowercase PHP file extensions were blocked. NOTE: this issue exists because of an incomplete fix for CVE-2020-28328.
Technical Analysis
CVE-2021-42840 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.
A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 8.8.
A proof-of-concept (PoC) exploit exists for CVE-2021-42840. While not yet confirmed in active campaigns, the availability of PoC code increases exploitation risk substantially.
CVSS v3.1 Vector Breakdown
Affected Vendors & Products
Exploit & PoC Resources
Official Patches & Advisories
All References (10)
Quick Facts
Related CVEs (CWE-434)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2021-42840 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts