Description

Sliver is an open source cross-platform adversary emulation/red team framework, it can be used by organizations of all sizes to perform security testing. The reverse port forwarding in sliver teamserver allows the implant to open a reverse tunnel on the sliver teamserver without verifying if the operator instructed the implant to do so. The only impact that has been shown is the exposure of the server's IP address to a third party. This issue has been addressed in version 1.5.43 and all users are advised to upgrade. There are no known workarounds for this vulnerability.

Classification

CVE ID: CVE-2025-27090

CVSS Base Severity: MEDIUM

CVSS Base Score: 6.9

CVSS Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N

Affected Products

Vendor: BishopFox

Product: sliver

Exploit Prediction Scoring System (EPSS)

EPSS Score: 0.04% (probability of being exploited)

EPSS Percentile: 9.24% (scored less or equal to compared to others)

EPSS Date: 2025-03-20 (when was this score calculated)

References

https://github.com/BishopFox/sliver/security/advisories/GHSA-fh4v-v779-4g2w
https://github.com/BishopFox/sliver/commit/0f340a25cf3d496ed870dae7da39eab4427bc16f
https://github.com/BishopFox/sliver/commit/10e245326070c6a5884a02e0790bb7e2baefb3a1

Timeline