CVE-2026-8328
📛 CVE Title
FTP PASV SSRF, ftpcp() does not use actual peer address, trusts server-supplied PASV host address
Description
The ftpcp() function in Lib/ftplib.py was not updated when CVE-2021-4189 was fixed. While makepasv() was patched to replace server-supplied PASV host addresses with the actual peer address (getpeername()[0]), ftpcp() still calls parse227() directly and passes the raw attacker-controllable IP address and port to target.sendport(). This patch is related to CVE-2021-4189.
Overview
- State
- PUBLISHED
- Assigner (CNA)
- PSF
- CVSS severity
- MEDIUM
- CVSS score
- 5.9 / 10
- CVSS vector
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N- Effective score
- 5.9 / 10 MEDIUM source: CNA overview
- CWE(s)
-
CWE-918 - Reserved
- 2026-05-11
- Published
- 2026-05-13 22:14 UTC
- Last updated
- 2026-05-14 14:49 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/8xxx/CVE-2026-8328.json
- Linked Threat
- CVE-2026-8328 — CVE-2026-8328
NVD triage scoring NVD CVE 2.0
Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.
- NVD published
- 2026-05-13 21:16:50 UTC
- NVD last modified
- 2026-05-14 16:21:23 UTC
- EPSS score
- 0.0005 (probability of exploitation in next 30 days)
- EPSS percentile
- 15.95% vs all CVEs — higher = more likely to be exploited, as of 2026-05-24
NVD / KEV / EPSS data refreshed 2026-05-25 06:17 UTC. Re-run the 🛰 Backfill from NVD button above to refresh.
European Union Vulnerability Database ENISA EUVD
ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.
- EUVD ID
-
EUVD-2026-30177 - Assigner
- PSF
- Published
- May 13, 2026, 8:14:33 PM
- Updated
- May 14, 2026, 12:49:39 PM
- EUVD base score (CVSS 4.0)
-
5.9 / 10
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N - EUVD-reported EPSS
- 0.0500
- Vendors
- Python Software Foundation
- Products
-
CPython (0 <3.15.0)
ENISA description: The ftpcp() function in Lib/ftplib.py was not updated when CVE-2021-4189 was fixed. While makepasv() was patched to replace server-supplied PASV host addresses with the actual peer address (getpeername()[0]), ftpcp() still calls parse227() directly and passes the raw attacker-controllable IP address and port to target.sendport(). This patch is related to CVE-2021-4189.
Microsoft Security Response Center MSRC
Microsoft's vendor-authoritative record from the Security Update Guide — its own CVSS score, impact, severity rating, exploit assessment, and KB-article fixes. Refreshed 2026-07-28 03:00 UTC (source: CVRF).
- MS severity
- Moderate
- Release
- 2026-May
Microsoft remediations / KB articles (2)
- CBL-Mariner Releases — Vendor Fix / Security Update (fixed build 3.12.9-12)
- https://learn.microsoft.com/en-us/azure/azure-linux/tutorial-azure-linux-upgrade — None Available / CBL-Mariner Releases
Affected products (1)
| Vendor | Product | Versions | Platforms |
|---|---|---|---|
| Python Software Foundation | CPython |
0 (affected)
|
— |
Vendor references (3)
References embedded in the original CVE record by the assigning CNA.
MITRE references (3) cveawg.mitre.org
Pulled from MITRE's CVE Services API by the 🛰 Backfill from MITRE button.
Web references (5)
DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.
- None Available msrc
- MSRC update guide: CVE-2026-8328 msrc
- https://www.first.org/epss/ tenable:www.first.org
- https://nvd.nist.gov/vuln/detail/CVE-2026-8328 tenable:nvd.nist.gov
- https://www.cve.org/CVERecord?id=CVE-2026-8328 tenable:www.cve.org
NVD-tagged references (3)
Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.
Remediations (16)
Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.
-
web:blog.talosintelligence.com
Microsoft has released its monthly security update for May 2026 , which includes 137 vulnerabilities affecting a range of products, including 16 that Microsoft marked as "critical".
2026-05-23 20:54 UTC -
web:cyberpress.org
The U.S. Cybersecurity and Infrastructure Security Agency (CISA) has added two actively exploited Microsoft Defender vulnerabilities to its Known Exploited Vulnerabilities (KEV) catalog, issuing an urgent remediation directive for federal agencies with a due date of June 3, 2026 .
2026-05-23 20:54 UTC -
web:cybersecuritynews.com
Microsoft's May 2026 Patch Tuesday lands with a heavy enterprise focus, fixing 120 vulnerabilities across Windows, Office, Azure, developer tools, and Microsoft 365 apps, including 29 remote code execution (RCE) flaws rated Critical.
2026-05-23 20:54 UTC -
web:krebsonsecurity.com
Microsoft expects that exploitation is more likely. May's Patch Tuesday is a welcome respite from April, which saw Microsoft fix a near-record 167 security flaws.
2026-05-23 20:54 UTC -
web:portal.msrc.microsoft.com
The Security Update Guide provides information on the latest Microsoft security updates, helping users understand and address potential vulnerabilities effectively.
2026-05-23 20:54 UTC -
web:support.microsoft.com
This non-security update for Windows 11, version 25H2 and 24H2 (KB5083631), includes production-quality improvements. To learn more about differences between security updates, optional non-security preview updates, out-of-band (OOB) updates, and continuous innovation, see Windows monthly updates explained. For information on Windows update terminology, see the different types of Windows ...
2026-05-23 20:54 UTC -
web:thecyberexpress.com
Microsoft Patch Tuesday: Zero-Day Vulnerabilities in Focus A major focus of this Patch Tuesday April 2026 cycle is the remediation of two zero-day vulnerabilities. One of the most concerning issues is an actively exploited spoofing vulnerability in Microsoft SharePoint Server.
2026-05-23 20:54 UTC -
web:vulert.com
Microsoft's May 2026 Patch Tuesday fixes 138 vulnerabilities, including critical Windows DNS and Netlogon RCE flaws. Learn the risks, key CVEs , mitigation steps, and how Vulert can help.
2026-05-23 20:54 UTC -
web:www.crowdstrike.com
Microsoft has released security updates for 130 vulnerabilities, including 30 critical, in its May 2026 Patch Tuesday rollout.
2026-05-23 20:54 UTC -
web:zecurit.com
Get the complete breakdown of Microsoft's May 2026 Patch Tuesday. We analyze the latest security updates and all critical CVEs .
2026-05-23 20:54 UTC -
web:community.ui.com
Published: May 21, 2026 Updated: May 22, 2026 Version: 1.1 Revision: 1.1 Summary 1 of 5 A malicious actor with access to the network and high privileges could exploit an Improper Input Validation vulnerability found in UniFi OS devices to execute a Command Injection. Affected Products: UniFi OS Server (Version 5.0.6 and earlier) Mitigation : Update your UniFi OS Server to Version 5.0.8 or later ...
2026-05-26 02:55 UTC -
web:cybersecuritynews.com
Microsoft released its March 2026 Patch Tuesday security update on March 10, 2026 , addressing 78 vulnerabilities across Windows, Microsoft Office, Azure, SQL Server, and .NET. The update includes one actively exploited zero-day vulnerability and multiple Critical-rated flaws demanding immediate attention from security teams. The most urgent fix this month is CVE - 2026 -21262, the sole zero-day ...
2026-05-26 02:55 UTC -
web:techdocs.broadcom.com
Patch Category Security Patch Severity Critical Host Reboot Required Yes Virtual Machine Migration or Shutdown Required Yes Affected Hardware N/A Affected Software N/A Affected VIBs Included VMware_bootbank_esxio-update_8..3-.60.24585383 VMware_bootbank_loadesxio_8..3-.60.24585383 PRs Fixed N/A CVE numbers N/A Due to their dependency on the ...
2026-05-26 02:55 UTC -
web:www.bleepingcomputer.com
Today is Microsoft's March 2026 Patch Tuesday with security updates for 79 flaws, including 2 publicly disclosed zero-day vulnerabilities.
2026-05-26 02:55 UTC -
web:www.cisecurity.org
<p>Multiple vulnerabilities have been discovered in Microsoft products, the most severe of which could allow for remote code execution. Successful exploitation of the most severe of these vulnerabilities could result in an attacker gaining the same privileges as the logged-on user. Depending on the privileges associated with the user, an attacker could then install programs; view, change, or ...
2026-05-26 02:55 UTC -
web:www.oracle.com
This Critical Patch Update contains 481 new security patches across the product families listed below. Please note that an MOS note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at April 2026 Critical Patch Update: Executive Summary and Analysis.
2026-05-26 02:55 UTC
AI Forensic Analysis
Only Available for Registered Users. Sign in to view.
Raw JSON
The full cvelistV5 record. Download as CVE-2026-8328.json.
{
"containers": {
"adp": [
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2026-8328",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "no"
},
{
"Technical Impact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-05-14T12:49:18.311219Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-05-14T12:49:39.908Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"modules": [
"ftplib"
],
"product": "CPython",
"repo": "https://github.com/python/cpython",
"vendor": "Python Software Foundation",
"versions": [
{
"lessThan": "3.15.0",
"status": "affected",
"version": "0",
"versionType": "python"
}
]
}
],
"credits": [
{
"lang": "en",
"type": "reporter",
"value": "Qi Deng (https://github.com/ikow)"
},
{
"lang": "en",
"type": "remediation developer",
"value": "B\u00e9n\u00e9dikt Tran (https://github.com/picnixz)"
},
{
"lang": "en",
"type": "remediation developer",
"value": "Gregory P. Smith (https://github.com/gpshead)"
}
],
"descriptions": [
{
"lang": "en",
"supportingMedia": [
{
"type": "text/html",
"value": "<div>The ftpcp() function in Lib/ftplib.py was not updated when \nCVE-2021-4189 was fixed. While makepasv() was patched to replace \nserver-supplied PASV host addresses with the actual peer address \n(getpeername()[0]), ftpcp() still calls parse227() directly and passes \nthe raw attacker-controllable IP address and port to target.sendport(). This patch is related to CVE-2021-4189.</div>"
}
],
"value": "The ftpcp() function in Lib/ftplib.py was not updated when \nCVE-2021-4189 was fixed. While makepasv() was patched to replace \nserver-supplied PASV host addresses with the actual peer address \n(getpeername()[0]), ftpcp() still calls parse227() directly and passes \nthe raw attacker-controllable IP address and port to target.sendport(). This patch is related to\u00a0CVE-2021-4189."
}
],
"metrics": [
{
"cvssV4_0": {
"Automatable": "NOT_DEFINED",
"Recovery": "NOT_DEFINED",
"Safety": "NOT_DEFINED",
"attackComplexity": "LOW",
"attackRequirements": "PRESENT",
"attackVector": "NETWORK",
"baseScore": 5.9,
"baseSeverity": "MEDIUM",
"exploitMaturity": "NOT_DEFINED",
"privilegesRequired": "NONE",
"providerUrgency": "NOT_DEFINED",
"subAvailabilityImpact": "NONE",
"subConfidentialityImpact": "NONE",
"subIntegrityImpact": "NONE",
"userInteraction": "ACTIVE",
"valueDensity": "NOT_DEFINED",
"vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N",
"version": "4.0",
"vulnAvailabilityImpact": "NONE",
"vulnConfidentialityImpact": "NONE",
"vulnIntegrityImpact": "HIGH",
"vulnerabilityResponseEffort": "NOT_DEFINED"
},
"format": "CVSS",
"scenarios": [
{
"lang": "en",
"value": "GENERAL"
}
]
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-918",
"description": "CWE-918 Server-Side request forgery (SSRF)",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-05-13T20:21:23.294Z",
"orgId": "28c92f92-d60d-412d-b760-e73465c3df22",
"shortName": "PSF"
},
"references": [
{
"tags": [
"issue-tracking"
],
"url": "https://github.com/python/cpython/issues/87451"
},
{
"tags": [
"patch"
],
"url": "https://github.com/python/cpython/pull/149648"
},
{
"tags": [
"vendor-advisory"
],
"url": "https://mail.python.org/archives/list/security-announce@python.org/thread/ITF2BAPBQEPYK3LDMPRSY435JGNHYNDP/"
}
],
"source": {
"discovery": "UNKNOWN"
},
"title": "FTP PASV SSRF, ftpcp() does not use actual peer address, trusts server-supplied PASV host address"
}
},
"cveMetadata": {
"assignerOrgId": "28c92f92-d60d-412d-b760-e73465c3df22",
"assignerShortName": "PSF",
"cveId": "CVE-2026-8328",
"datePublished": "2026-05-13T20:14:33.751Z",
"dateReserved": "2026-05-11T15:06:00.859Z",
"dateUpdated": "2026-05-14T12:49:39.908Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}