DSUtility.dll in Pelco Digital Sentry Server before 7.19.67 has an arbitrary file write vulnerability. The AppendToTextFile method doesn't check if it's being called from the application or from a malicious user. The vulnerability is triggered when a remote attacker crafts an HTML page (e.g., with "OBJECT classid=" and "<SCRIPT language='vbscript'>") to overwrite arbitrary files.

References

• https://nvd.nist.gov/vuln/detail/CVE-2021-27197
• https://github.com/vitorespf/Advisories/blob/master/Pelco_Digital_Sentry_Server_AFW.txt
• https://support.pelco.com/s/article/What-is-the-Digital-Sentry-software-release-revision-history