CVE-2026-58085
Received
Received - Intake
WireGuard Poly1305 Authentication Bypass in FreeBSD wg(4) Driver
Vulnerability report for CVE-2026-58085, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-08-19
Last updated on: 2026-08-19
Assigner: FreeBSD
Description
Description
After dispatching a decrypt operation to OCF and receiving the result, the wg(4) driver failed to check whether the MAC verification step succeeded. The driver thus silently accepted packets with an invalid Poly1305 authentication tag.
A remote attacker who can send UDP packets to a WireGuard endpoint, and who can guess the bounds of the receiver's replay window, can inject forged or modified transport data packets into the tunnel.
A remote attacker who can intercept WireGuard packets bound for a FreeBSD host can modify the ciphertext and authenticated data without detection by the receiver.
CVSS Scores
EPSS Scores
| Probability: | |
| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| freebsd | freebsd | From 15.0 (inc) to 15.1 (inc) |
| freebsd | freebsd | 14.4 |
| wireguard | wireguard | * |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-347 | The product does not verify, or incorrectly verifies, the cryptographic signature for data. |
