Medium severity · published Oct 29, 2026
CVE-2026-90870
Unauthenticated Ad Hoc Transfer Resource Exhaustion in Progress WS_FTP Server
New
5.3
CVSS
–
EPSS
No
On KEV
Description
A missing release of backend receiver sessions in the Ad Hoc Transfer component of Progress Software WS_FTP Server versions prior to 2024.0.7 and 2025.0.4 on Windows could lead to server resource exhaustion and service degradation.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
WS
WS_FTP Server · Progress Software
before 2024.0.7; before 2025.0.4 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-90870
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-90870
vendor-advisory
https://progress.lightning.force.com/lightning/r/Knowledge__kav/ka7Pb000001vl86IAA/view
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