When Octopus Tentacle is installed using a custom folder location, folder ACLs are not set correctly and could lead to an unprivileged user…

published 2021-10-07 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-13356

cvss: 7.8; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 25%
public exploits: 0; none known

When Octopus Tentacle is installed using a custom folder location, folder ACLs are not set correctly and could lead to an unprivileged user using DLL side-loading to gain privileged access.

Patch / fix

fixed in 1

Octopus Deploy Octopus Tentacle 6.0.489

Exploit prediction

0.32% chance of exploitation in the next 30 days, higher than 25% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
NVD	3.1	7.8	CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
NVD	2.0	4.4	AV:L/AC:M/Au:N/C:P/I:P/A:P

Affected products

Octopus Deploy Octopus Tentacle

Classification

Weakness

CWE-426 Untrusted Search Path

References

advisories.octopus.com /adv/2021-02---Local-privilege-escalation-in-Octopus-Tentacle-%28CVE-2021-26557%29.1732870264.html

Sources

CVE List CVE-2021-26557
NVD CVE-2021-26557

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary