Unauthenticated Telnet Access in Calix GigaCenter ONT Products
CVE-2025-7635

8.7HIGH

Key Information:

Vendor

Calix

Status
Gigacenter Ont
Vendor
CVE Published:
9 September 2025

What is CVE-2025-7635?

The Telnet access vulnerability in Calix GigaCenter ONT devices allows unauthorized users to gain root access without authentication. This poses a serious security risk, potentially enabling attackers to manipulate device settings and compromise network integrity. Affected models include GigaCenter ONT 844E, 844G, 844GE, and 854GE, emphasizing the need for immediate attention and mitigation from users of these products.

Affected Version(s)

GigaCenter ONT 844E

GigaCenter ONT 844G

GigaCenter ONT 844GE

References

https://fluidattacks.com/advisories/sal
third-party-advisory
https://www.calix.com
productrelated

CVSS V4

Score:
8.7
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Adjacent Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.
CVE-2025-7635 : Unauthenticated Telnet Access in Calix GigaCenter ONT Products