CVE-2024-0840: Grandstream UCM Series IP PBX HTTP Parameter Injection

Severity: high (CVSS 8.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.9% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2024-04-29 · updated 2026-06-17
Weakness: CWE-141

Description

The Grandstream UCM Series IP PBX before firmware version 1.0.20.52 is affected by a parameter injection vulnerability in the HTTP interface. A remote and authenticated attacker can execute arbitrary code by sending a crafted HTTP request. Authentication may be possible using a default user and password. Affected models are the UCM6202, UCM6204, UCM6208, and UCM6510.

Affected products

Grandstream Ucm6202 Firmware: before 1.0.20.52 — fixed in 1.0.20.52
Grandstream Ucm6204 Firmware: before 1.0.20.52 — fixed in 1.0.20.52
Grandstream Ucm6208 Firmware: before 1.0.20.52 — fixed in 1.0.20.52
Grandstream Ucm6510 Firmware: before 1.0.20.52 — fixed in 1.0.20.52

How to fix

Upgrade to a fixed version: Grandstream Ucm6202 Firmware 1.0.20.52; Grandstream Ucm6204 Firmware 1.0.20.52; Grandstream Ucm6208 Firmware 1.0.20.52; Grandstream Ucm6510 Firmware 1.0.20.52. Check the vendor advisory for mitigations.

References

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