Calix GigaCenter ONT 844E/844G/844GE/854GE Telnet Service missing authentication

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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8.3$0-$5k0.00

Summaryinfo

A vulnerability has been found in Calix GigaCenter ONT 844E/844G/844GE/854GE and classified as critical. Affected by this vulnerability is an unknown functionality of the component Telnet Service. This manipulation causes missing authentication. The identification of this vulnerability is CVE-2025-7635. The attack needs to be done within the local network. There is no exploit available.

Detailsinfo

A vulnerability classified as critical was found in Calix GigaCenter ONT 844E/844G/844GE/854GE. Affected by this vulnerability is an unknown part of the component Telnet Service. The manipulation with an unknown input leads to a missing authentication vulnerability. The CWE definition for the vulnerability is CWE-306. The product does not perform any authentication for functionality that requires a provable user identity or consumes a significant amount of resources. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

Unauthenticated Telnet access vulnerability in Calix GigaCenter ONT allows root access.This issue affects GigaCenter ONT: 844E, 844G, 844GE, 854GE.

The advisory is shared at fluidattacks.com. This vulnerability is known as CVE-2025-7635 since 07/14/2025. The exploitation appears to be easy. The attack needs to be done within the local network. The exploitation doesn't need any form of authentication. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 12/23/2025).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

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Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 8.3
VulDB Meta Temp Score: 8.3

VulDB Base Score: 8.8
VulDB Temp Score: 8.8
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 7.7
NVD Vector: 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Missing authentication
CWE: CWE-306 / CWE-287
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

07/14/2025 CVE reserved
09/09/2025 +57 days Advisory disclosed
09/09/2025 +0 days VulDB entry created
12/23/2025 +105 days VulDB entry last update

Sourcesinfo

Advisory: fluidattacks.com
Status: Not defined

CVE: CVE-2025-7635 (🔒)
GCVE (CVE): GCVE-0-2025-7635
GCVE (VulDB): GCVE-100-323389

Entryinfo

Created: 09/09/2025 23:06
Updated: 12/23/2025 03:42
Changes: 09/09/2025 23:06 (65), 12/23/2025 03:42 (11)
Complete: 🔍
Cache ID: 216::103

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