ExtremeXOS Privilege Escalation via Symlink Following in File Utilities
Summary
| CVE | CVE-2026-8170 |
|---|---|
| State | PUBLISHED |
| Assigner | ExtremeNetworks |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-07-20 18:16:56 UTC |
| Updated | 2026-07-20 20:16:47 UTC |
| Description | The mv, cp, and rm file utilities exposed within the ExtremeXOS (EXOS) shell environment fail to safely canonicalize paths and follow symbolic links outside of the intended privilege boundary. An attacker with low-privilege CLI access can create a symbolic link that references a privileged filesystem location and then invoke the affected utilities to read, modify, or replace security-critical files outside of their authorized scope. Under certain conditions, this may enable escalation to root-level access and persistent modification of the device software stack. Exploitation is possible remotely by an attacker holding a low-privilege account, or locally via the serial console. Extreme would like to thank Hadrien Barral (Université Gustave Eiffel) and Georges-Axel Jaloyan (French Ministry of the Interior) for responsible disclosure of their findings. |
Risk And Classification
Primary CVSS: v4.0 8.7 HIGH from 1c053176-eef3-4d6a-ae0b-24728c86587b
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Problem Types: CWE-59 | CWE-59 CWE-59: Improper Link Resolution Before File Access ('Link Following')
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 4.0 | 1c053176-eef3-4d6a-ae0b-24728c86587b | Secondary | 8.7 | HIGH | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/C... |
| 4.0 | CNA | CVSS | 8.7 | HIGH | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N |
CVSS v4.0 Breakdown
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Extreme Networks | Switch Engine EXOS | affected 31.7.4 custom | Switch Engine |
| CNA | Extreme Networks | Switch Engine EXOS | affected 32.0.0 32.7.4.15 custom | Switch Engine |
| CNA | Extreme Networks | Switch Engine EXOS | affected 33.0.0 33.1.100 custom | Switch Engine |
| CNA | Extreme Networks | Switch Engine EXOS | affected 33.2.0 33.7.1 custom | Switch Engine |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| www.extremenetworks.com/support/policies/product-security | 1c053176-eef3-4d6a-ae0b-24728c86587b | www.extremenetworks.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: Extreme would like to thank Hadrien Barral (Université Gustave Eiffel) and Georges-Axel Jaloyan (French Ministry of the Interior) for responsible disclosure of their findings. (en)
Additional Advisory Data
Solutions
CNA: Extreme Networks has released fixed versions of Switch Engine (EXOS) that address this vulnerability. Customers should upgrade to one of the following releases or later: 31.7.4, 32.7.4.15, 33.1.100, or 33.7.1.
Workarounds
CNA: Where immediate upgrade is not feasible, customers should: (1) restrict CLI access to trusted administrators only; (2) enforce strong authentication and rotate any default credentials; (3) restrict physical access to serial console ports; and (4) monitor device logs for anomalous shell activity and filesystem modifications.