CVE-2021-47889
Published: 23 January 2026
Summary
CVE-2021-47889 is a high-severity Unquoted Search Path or Element (CWE-428) vulnerability in Softros LAN Messenger (inferred from references). Its CVSS base score is 8.5 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Path Interception by Unquoted Path (T1574.009); ranked at the 2.1th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
The strongest mitigations our analysis identified are NIST 800-53 CM-6 (Configuration Settings) and CM-7 (Least Functionality).
Deeper analysis
CVE-2021-47889 is an unquoted service path vulnerability in the SoftrosSpellChecker service of Softros LAN Messenger version 9.6.4. The issue arises from an unquoted path at 'C:\Program Files (x86)\Softros Systems\Softros Messenger\Spell Checker\', which allows local attackers to potentially execute arbitrary code by injecting malicious executables into that directory. It is classified under CWE-428 and carries a CVSS v3.1 base score of 7.8 (AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H).
Local attackers with low privileges can exploit this vulnerability through low-complexity attacks requiring no user interaction. Exploitation enables privilege escalation by hijacking the service execution, resulting in high impacts to confidentiality, integrity, and availability.
Advisories, including the Vulncheck advisory at https://www.vulncheck.com/advisories/softros-lan-messenger-softrosspellchecker-unquoted-service-path, detail the unquoted service path issue. A public exploit is available at https://www.exploit-db.com/exploits/49588, and the vendor site at https://www.softros.com/ provides relevant information.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-4305
Vulnerability details
Softros LAN Messenger 9.6.4 contains an unquoted service path vulnerability in the SoftrosSpellChecker service that allows local attackers to potentially execute arbitrary code. Attackers can exploit the unquoted path in 'C:\Program Files (x86)\Softros Systems\Softros Messenger\Spell Checker\' to inject malicious executables…
more
and escalate privileges.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Unquoted service path in SoftrosSpellChecker directly enables path interception by placing a malicious executable in the partial path directory, hijacking service execution for privilege escalation.
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
CM-6 enforces and documents secure configuration settings for system components, directly preventing unquoted service path vulnerabilities by requiring properly quoted executable paths for services like SoftrosSpellChecker.
SI-2 requires identification, reporting, and timely remediation of system flaws, including patching Softros LAN Messenger to fix the unquoted service path issue.
CM-7 restricts systems to least functionality required, enabling disablement of non-essential services like SoftrosSpellChecker to eliminate the vulnerable attack surface.