Medium severity · published Jun 4, 2026
CVE-2026-4881
In affected versions of Octopus Server, permissions were not checked correctly resulting in any authenticated user being able to make server level changes using a certain API…
6.5
CVSS
0.2%
EPSS
No
On KEV
Description
In affected versions of Octopus Server, permissions were not checked correctly resulting in any authenticated user being able to make server level changes using a certain API endpoint despite receiving an error.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 11% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
OS
Octopus Server · Octopus Deploy
2023.0.0 before 2025.4.10523; 2025.4.0 before 2025.4.10545; 2026.1.0 before 2026.1.11313 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-4881
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-4881
Vendor Advisory
https://advisories.octopus.com/post/2026/sa2026-04
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