What is CVE-2015-3306?

CVE-2015-3306 is ProFTPD Improper Access Control Vulnerability. The supplied enrichment data classifies it as Access Control mapped to CWE-284 Improper Access Control.

Which versions are affected?

Affected product and version evidence is listed in the product table above. Current public advisories should be checked for exact version scope before patch targeting is finalized.

Is there active exploitation?

Yes: CISA KEV signal present. If exploitation is not confirmed from current sources, teams should document that status and continue monitoring KEV, vendor, and telemetry updates.

Is there a public exploit?

408 public PoC repositories reported; 3 marked weaponized in current dataset. Public exploit or PoC availability should raise triage priority, especially for exposed or business-critical systems.

How can defenders detect it?

Start with web/proxy/WAF logs, application logs, network IDS/IPS where available. Look for vulnerability-class behavior, product errors, suspicious authentication events, exploit probes, and abnormal process activity based only on evidence that applies to the affected product.

How should teams prioritize it?

Prioritize CVE-2015-3306 using CVSS 10, EPSS 97%, KEV status, public PoC status, and asset exposure. Internet-facing, privileged, or business-critical deployments should be handled first.

Are workarounds available?

The supplied mitigation guidance says to apply vendor patches and restrict external exposure until fixed. Fixed-version evidence is listed in the mitigation section above.

Which threat actors are linked publicly?

No public threat actor linkage is confirmed from current sources. Do not attribute exploitation to a threat actor unless the source evidence explicitly supports that linkage.

What should be done in the next 24 hours?

Identify exposed assets running affected vendor/product/version combinations. Treat as emergency remediation because CISA KEV status is present. Search available logs for exploit probes, errors, authentication anomalies, or suspicious child processes matching the vulnerability class. Open remediation tickets with affected assets, owners, evidence status, and detection coverage so decisions are traceable.

CISA KEVhighAccess Controlpublic exploit

CVE-2015-3306

CVE-2015-3306 — ProFTPD Improper Access Control Vulnerability

Q: Is it in CISA KEV?

Yes. The supplied enrichment data lists CVE-2015-3306 in CISA KEV with required action: 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.. KEV status should be monitored because it can change after initial disclosure or after exploitation becomes publicly confirmed.

The mod_copy module in ProFTPD 1.3.5 allows remote attackers to read and write to arbitrary files via the site cpfr and site cpto commands.

Published May 18, 2015Updated Oct 8, 2026Sources: NVD, ProFTPD (CNA), CISA, FIRST EPSS, GitHub, Exploit-DB, Red Hat (VEX), SOCRadar CTI

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the scoring sources call it.

Exploitation

Confirmed

CISA KEV, listed Oct 8, 2026

EPSS

97%

ahead of 99.9% of scored CVEs

Affects

ProFTPD

CVSS base

high · 3 sources

Remediation

The vendor's own words where we have them.

Upgrade ProFTPD to a fixed release. Apply vendor patches per advisory and restrict external exposure of the affected component until patched.

CISA required action

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.

Federal deadline Oct 11, 2026 — in 2 days

Red Hat VEX · CVE-2015-3306

fixed0affected0not affected1

First 24 hours

Ordered from the record's own fields — exposure first, because you cannot patch what you have not found.

Identify exposed assets running affected vendor/product/version combinations.
Treat as emergency remediation because CISA KEV status is present.
Search available logs for exploit probes, errors, authentication anomalies, or suspicious child processes matching the vulnerability class.

Affected scope

Vendor, product and version as the advisories word them.

Vendor	Product	Versions	Status
ProFTPD	ProFTPD	—	Vulnerable

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Availability

Changed

Confidentiality

Changed

Integrity

Changed

Attack Complexity

Low

Attack Vector

Network

Every base score collected

Sources score independently and disagree; each row says who scored it and under which version.

Score	Version	Severity	Expl.	Impact	Source
10	CVSS 3.1	critical	3.9	6	CNA
10	CVSS 2.0	high	10	10	NVD
7.8	CVSS 3.1	high	—	—	Red Hat (VEX)

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

What this weakness leads to

MITRE's own consequences and mitigations for the weakness class — the authority's wording, not guidance derived from the CVSS vector.

MITRE

CWE-284 · Improper Access Control

Varies by Context::

Mitigation: Very carefully manage the setting, management, and handling of privileges. Explicitly manage trust zones in the software.

Weakness & attack patterns

CWE-284Improper Access Control

Attack patterns reported against this CVE. The ATT&CK techniques below are inferred from its weakness class.

CAPEC-562 · Modify Shared FileCAPEC-19 · Embedding Scripts within ScriptsCAPEC-503 · WebView ExposureCAPEC-441 · Malicious Logic InsertionCAPEC-563 · Add Malicious File to Shared WebrootCAPEC-478 · Modification of Windows Service ConfigurationCAPEC-479 · Malicious Root CertificateCAPEC-502 · Intent SpoofCAPEC-536 · Data Injected During ConfigurationCAPEC-546 · Probe Application MemoryCAPEC-550 · Install New ServiceCAPEC-551 · Modify Existing Service

T1027.009Obfuscated Files or Information: Embedded Payloads
T1546.004Event Triggered Execution: .bash_profile and .bashrc
T1546.016Event Triggered Execution: Installer Packages

CISA KEV details

CISA lists a CVE here once it has evidence of exploitation against real targets.

CISAThat month →

Listed

Oct 8, 2026

Federal deadline

Oct 11, 2026

in 2 days

Ransomware use

Unknown

CISA records ransomware use only for campaigns it has confirmed, so “Unknown” means unrecorded, not ruled out. The deadline binds US federal agencies; for everyone else it is a date to argue against.

Public exploit

Capability, not use: code existing is a different claim from anyone running it.

Repositories

387

3 of the 5 sampled are weaponized

Exploit entries

Exploit-DB and CTI exploit indexes

Social mentions

Posts naming this CVE. Attention, not evidence of exploitation — it spikes on disclosure and decays whether or not anything is exploited.

FTP is still alive — and still getting pwned. From invisible Nmap scans to root RCE via CVE-2011-2523 & CVE-2015-3306, legacy FTP is a silent gateway. Full Metasploit guide: https://t.co/w4WUfBgNqx #Metasploit #FTP #InfoSec #Pentesting #CyberSecurity https://t.co/UcdblbmXe8
@HackerrsNews· Oct 6, 2026

EPSS over time

FIRST rescores it daily; this is its history for as long as we have been tracking this CVE.

FIRST

Sep 8, 2026 → Oct 7, 2026 · 30 days

Detection

Read off the CVSS vector and the weakness class. Starting points, not rules we have tested.

Prioritize edge telemetry for network-reachable ProFTPD.
Monitor for scanner or exploit-pattern traffic after 408 public PoC repositories were reported.

web/proxy/WAF logsapplication logsnetwork IDS/IPS

Groups associated with this CVE

Groups reported in connection with this vulnerability. A reported association, not a confirmed observation of that group using it — and not scoped to any sector or campaign.

hostnamereal-websolutions.nl53
Zonefiles · Jun 5, 2020
ip187.9.92.19034
Blocklist.de-Firehol-Potential Attackers · Apr 28, 2025
hostname4t-niagara.com60
SOCRadar Threat Exchange Services · Feb 19, 2026
ip200.27.110.2938
socks-proxy-Firehol · Aug 26, 2020
ip195.177.217.13136
KillNet-DDoS-Blocklist · Oct 11, 2021

5 more indicators on this CVEShowing 5 of 10 · Hashes, addresses and domains from a live threat exchangeUnlock free

Timeline

What happened to this CVE, newest first — with the readings a source repeats on a schedule counted underneath rather than listed.

2026
Added to CISA KEV catalog
Oct 8, 2026 · CISA
Added · CVSS 3.1 10.0 (AV:N)
Oct 8, 2026 · NVD
Cve is exploited canpilayda/proftpd-mod_copy-cve-2015-3306
Jan 23, 2026 · SOCRadar CTI
2025
Cve is exploited Z3R0-0x30/CVE-2015-3306
May 21, 2025 · SOCRadar CTI
2023
CVE is exploited. "0xT11/CVE-POC"
Dec 15, 2023 · SOCRadar CTI
CVE is exploited. "ARPSyndicate/cvemon"
Dec 15, 2023 · SOCRadar CTI
CVE is exploited. "GhostTroops/TOP"
Dec 15, 2023 · SOCRadar CTI
CVE is exploited. "jbmihoub/all-poc"
Dec 15, 2023 · SOCRadar CTI
CVE is exploited. "cd6629/CVE-2015-3306-Python-PoC"
Dec 15, 2023 · SOCRadar CTI
CVE is exploited. "cdedmondson/Modified-CVE-2015-3306-Exploit"
Dec 15, 2023 · SOCRadar CTI
CVE is exploited. "developer3000S/PoC-in-GitHub"
Dec 15, 2023 · SOCRadar CTI
CVE is exploited. "hectorgie/PoC-in-GitHub"
Dec 15, 2023 · SOCRadar CTI
CVE is exploited. "nootropics/propane"
Dec 15, 2023 · SOCRadar CTI
CVE is exploited. "qazbnm456/awesome-cve-poc"
Dec 15, 2023 · SOCRadar CTI
CVE is exploited. "shk0x/cpx_proftpd"
Dec 15, 2023 · SOCRadar CTI
CVE is exploited. "t0kx/exploit-CVE-2015-3306"
Dec 15, 2023 · SOCRadar CTI
CVE is exploited. "xbl3/awesome-cve-poc_qazbnm456"
Dec 15, 2023 · SOCRadar CTI
CVE is exploited. "xchg-rax-rax/CVE-2015-3306-"
Nov 25, 2023 · SOCRadar CTI
2021
Added · Verified remote entry: ProFTPd 1.3.5 - 'mod_copy' Remote Command Execution (2)
May 26, 2021 · Exploit-DB
2015
Added · Verified remote entry: ProFTPd 1.3.5 - 'mod_copy' Command Execution (Metasploit)
Jun 10, 2015 · Exploit-DB
Initial · CVE published
May 18, 2015 · NVD
Added · remote entry: ProFTPd 1.3.5 - 'mod_copy' Remote Command Execution
Apr 21, 2015 · Exploit-DB

Source activity

Readings a source repeats on a schedule, counted rather than listed.

13×SvrsFeb 13, 2024 – Jan 23, 2026 · SOCRadar CTI
8×Github ReposOct 24, 2023 – Jan 18, 2026 · SOCRadar CTI
1×CVE modified by NIST: CISA KEV details updated.Oct 8, 2026 · SOCRadar CTI
1×Tweets · 1 time tweeted.Oct 7, 2026 · SOCRadar CTI
1×2 times mentioned on 2 Telegram channelsNov 29, 2025 · SOCRadar CTI

References

25 on the record

lists.fedoraproject.org/pipermail/package-announce/2015-May/157053.html
Vendor Advisory
lists.fedoraproject.org/pipermail/package-announce/2015-May/157054.html
Vendor Advisory
lists.fedoraproject.org/pipermail/package-announce/2015-May/157581.html
Vendor Advisory
lists.opensuse.org/opensuse-updates/2015-06/msg00020.html
Vendor Advisory, Mitre, NIST
packetstormsecurity.com/files/131505/ProFTPd-1.3.5-File-Copy.html
Vendor Advisory, MITRE_REFERENCES, GITHUB, NIST
packetstormsecurity.com/files/131555/ProFTPd-1.3.5-Remote-Command-Execution.html
Vendor Advisory, MITRE_REFERENCES, GITHUB, NIST
packetstormsecurity.com/files/131567/ProFTPd-CPFR-CPTO-Proof-Of-Concept.html
Vendor Advisory, GITHUB, MITRE_REFERENCES, NIST
packetstormsecurity.com/files/132218/ProFTPD-1.3.5-Mod_Copy-Command-Execution.html
Vendor Advisory, MITRE_REFERENCES, GITHUB, NIST

Elsewhere on this site

ProFTPDevery CVE for this vendor
October 2026what else CISA listed
Access Controlsame class
CWE-284other pages naming this weakness

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

Only the 5 indicator(s) reported for this CVE are available; no packet-level or host-forensic artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record1

What should defenders know first?

CVE-2015-3306 is ProFTPD Improper Access Control Vulnerability, a high vulnerability affecting ProFTPD from ProFTPD. The current evidence lists it in CISA KEV, and the exploit status is: Yes: CISA KEV signal present. Public exploit evidence is: 408 public PoC repositories reported; 3 marked weaponized in current dataset. The affected-version evidence is listed in the key facts and affected products tables. Defenders should first verify whether exposed or business-critical assets run those versions, then apply vendor patches or mitigations, restrict reachable attack surface, and preserve logs for detection review. CVSS 10 describes technical severity, while EPSS 97% helps estimate near-term exploit likelihood; neither replaces asset context. Unknown fields should remain explicit in tickets, and threat actor, IOC, victimology, or payload claims should not be added unless a cited source supports them. Monitor CISA KEV, vendor advisories, NVD changes, public PoC repositories, and internal telemetry for update triggers.