TI-2026-81098 Aliases CVE-2026-117341 GHSA-gfh4-mmcc-43wr

Octopus Server writes user invitation codes to the audit event log

LOW 35CWE-532Published 2026-10-27 · Updated 2026-11-04

Key facts

Attack vector: Network
Privileges required: Low
User interaction: None
Attack complexity: Low
Attack requirements: Present
Impact type: Information disclosure
Confidentiality · integrity · availability: High · High · High
Fix status: Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-532.

Summary

Octopus Server from 2019.0.0 before 2026.2.13438 and from 2026.3.0 before 2026.3.15829 writes the invitation code to the audit event log when a user invitation is created. Insertion of sensitive information into a log file (CWE-532) lets a user in the linked space with appropriate permissions read the code from the audit event. An attacker who redeems the unclaimed invitation could escalate privileges, depending on the permissions assigned to the invited user, and the attacker needs low privileges.

Written with Claude Haiku 5.5 from the sources below · 2026-11-04

Description from the CNA

In affected versions of Octopus Server, creating a user invitation writes the invitation code to the audit event log. When the invitation is linked to a space, a user in that space with appropriate permissions could read the code from the audit event. Successfully exploiting this by redeeming the unclaimed invitation could allow the user to escalate privileges however this is dependant on the permissions assigned for the invited user.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00226 13th percentileScored 2026-11-07

Fix Fixed Octopus Server (Octopus Deploy): 2026.2.13438, 2026.3.15829

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: No
Technical impact: Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
Octopus Deploy	Octopus Server	2019.0.0 to before 2026.2.13438; 2026.3.0 to before 2026.3.15829	2026.2.13438, 2026.3.15829	Patch available	CNA

Octopus Server VendorOctopus Deploy Affected 2019.0.0 to before 2026.2.13438; 2026.3.0 to before 2026.3.15829 Fixed in 2026.2.13438, 2026.3.15829 Patch available CNA

Remediation

Upgrade Octopus Server to 2026.2.13438 or 2026.3.15829. The sources list no further advisory identifiers for this fix.

Written with Claude Haiku 5.5 from the sources below · 2026-11-04

Fix · CNA Octopus Server (Octopus Deploy) Fixed in 2026.2.13438, 2026.3.15829

Timeline

2026-10-27 Threatist record created from CVE-2026-117341
2026-10-27 Alias added: GHSA-gfh4-mmcc-43wr
2026-10-28 Priority changed: MEDIUM → LOW
2026-11-04 CISA SSVC decision points changed

References

Other 1

https://advisories.octopus.com/post/2026/sa2026-16

TI-2018-13353 In Octopus Deploy 2018.8.0 through 2018.9.x before 2018.9.1, an authenticated user with… CVSS 3.0HIGH 8.8
TI-2022-02375 Improper authentication in Octopus Server CVSS 3.1CRITICAL 9.8
TI-2022-02579 Insufficient session expiration in Octopus Server CVSS 3.1CRITICAL 9.1
TI-2021-11816 Deserialization of untrusted data in Octopus Deploy Halibut CVSS 3.1CRITICAL 9.8
TI-2018-08066 In Octopus Deploy 2018.4.4 through 2018.5.1, Octopus variables that are sourced from the… CVSS 3.0CRITICAL 9.8
TI-2022-02575 In affected versions of Octopus Deploy it is possible to bypass rate limiting on login using null bytes. CVSS 3.1CRITICAL 9.8

See all 117 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences