CVE-2026-27899

CVE-2026-27899 is a high-severity vulnerability in Wgportal Wireguard Portal with a CVSS 3.x base score of 8.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-863.

Key facts

Description

WireGuard Portal (or wg-portal) is a web-based configuration portal for WireGuard server management. Prior to version 2.1.3, any authenticated non-admin user can become a full administrator by sending a single PUT request to their own user profile endpoint with `"IsAdmin": true` in the JSON body. After logging out and back in, the session picks up admin privileges from the database. When a user updates their own profile, the server parses the full JSON body into the user model, including the `IsAdmin` boolean field. A function responsible for preserving calculated or protected attributes pins certain fields to their database values (such as base model data, linked peer count, and authentication data), but it does not do this for `IsAdmin`. As a result, whatever value the client sends for `IsAdmin` is written directly to the database. After the exploit, the attacker has full admin access to the WireGuard VPN management portal. The problem was fixed in v2.1.3. The docker images for the tag 'latest' built from the master branch also include the fix.

Frequently asked questions

What is CVE-2026-27899?
WireGuard Portal (or wg-portal) is a web-based configuration portal for WireGuard server management. Prior to version 2.1.3, any authenticated non-admin user can become a full administrator by sending a single PUT request to their own user profile endpoint with `"IsAdmin": true` in the JSON body. After logging out and back in, the session picks up admin privileges from the database. When a user updates their own profile, the server parses the full JSON body into the user model, including the `IsAdmin` boolean field. A function responsible for preserving calculated or protected attributes pins certain fields to their database values (such as base model data, linked peer count, and authentication data), but it does not do this for `IsAdmin`. As a result, whatever value the client sends for `IsAdmin` is written directly to the database. After the exploit, the attacker has full admin access to the WireGuard VPN management portal. The problem was fixed in v2.1.3. The docker images for the tag 'latest' built from the master branch also include the fix.
How severe is CVE-2026-27899?
CVE-2026-27899 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-27899 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (22nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-27899?
CVE-2026-27899 affects Wgportal Wireguard Portal. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-27899?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-27899 have an EU (EUVD) identifier?
Yes. CVE-2026-27899 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-8797.
When was CVE-2026-27899 published?
CVE-2026-27899 was published on 2026-02-26 and last updated on 2026-06-17.

References

Affected products (1)

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