The US Cybersecurity and Infrastructure Security Agency (CISA) added CVE-2015-3306, a ProFTPD Improper Access Control Vulnerability, to its Known Exploited Vulnerabilities (KEV) catalog on October 8, 2026. CISA adds a flaw to the catalog when it has reliable evidence that attackers are exploiting it in the wild.
What CISA says
ProFTPD contains an improper access control vulnerability that could allow remote attackers to read and write to arbitrary files via the site cpfr and site cpto commands.
— CISA KEV catalog entry for CVE-2015-3306
Key facts
| CVE | CVE-2015-3306 |
|---|---|
| Vendor / product | ProFTPD |
| Added to KEV | October 8, 2026 |
| Federal deadline | October 11, 2026 |
| Known ransomware use | Unknown |
| Weakness (CWE) | CWE-284 |
| CISA forensic triage | Yes |
| CVSS base score (NVD) | 10 Critical |
| CVSS vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H |
Who has to act, and by when
US federal civilian executive branch agencies are required to remediate the vulnerability by October 11, 2026. CISA urges all organizations to prioritize KEV-listed flaws as part of their vulnerability management.
CISA’s required action for this entry:
Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
References
- CISA Known Exploited Vulnerabilities Catalog https://www.cisa.gov/known-exploited-vulnerabilities-catalog
- NIST NVD — CVE-2015-3306 https://nvd.nist.gov/vuln/detail/CVE-2015-3306
- www.proftpd.org http://www.proftpd.org/
- lists.debian.org https://lists.debian.org/debian-security-announce/2015/msg00154.html
- lists.opensuse.org https://lists.opensuse.org/archives/list/updates@lists.opensuse.org/message/WE6YZRG5UVXMGQ7IVDRYBPIWV4M6UUGM/
- www.cisa.gov https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk
- www.cisa.gov https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk