VulnerabilityPublished 2 Jul 2025

CVE-2025-27026: Infinera G42 · Insufficient Granularity of Access Control

Affects Infinera G42Source CVE Database V5

Not known to be exploited · CVSS 4.9 Medium.

Data as of 26 Oct 2026, 14:05 UTC

CVSS 3.1 base score

4.9Medium

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.3% chance of exploitation in 30 days – higher than 31% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H

Attack Vector: Network
Attack Complexity: Low
Privileges Required: High
User Interaction: None
Scope: Unchanged
Confidentiality: None
Integrity: None
Availability: High

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: High: The attacker is authorized with (i.e., requires) privileges that provide significant (e.g., administrative) control over the vulnerable component that could affect component-wide settings and files.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: None: There is no loss of confidentiality within the impacted component.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: High: There is total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable).

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 2 Jul 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Affected software

Product	Affected	Fixed in
Infinera G42	Affected =6.1.3	Fixed in–

AI-suggested

To mitigate this vulnerability, European organizations should implement the following specific measures: 1) Restrict administrative access to the Infinera G42 WebGUI to trusted personnel only, using strong authentication mechanisms and network segmentation to limit exposure. 2) Establish strict operational procedures and change management controls that require peer review or dual authorization before performing critical actions such as CLI deactivation. 3) Train administrators about the risk of this vulnerability and the importance of avoiding the CLI deactivation function unless absolutely necessary. 4) Where possible, maintain out-of-band management channels or redundant access paths (e.g., separate console servers or secure serial connections) to regain control if the primary interfaces are disabled. 5) Monitor device logs and management activity for unusual or unauthorized attempts to disable interfaces. 6) Engage with Infinera support to obtain patches or firmware updates addressing this issue as soon as they become available, and plan timely deployment. 7) Consider implementing automated backup and recovery procedures for device configurations to facilitate rapid restoration in case of lockout. These steps go beyond generic advice by focusing on operational controls, administrative discipline, and infrastructure redundancy tailored to the specific nature of this vulnerability.

Description

A missing double-check feature in the WebGUI for CLI deactivation in Infinera G42 version R6.1.3 allows an authenticated administrator to make other management interfaces unavailable via local and network interfaces. The CLI deactivation via the WebGUI does not only stop CLI interface but deactivates also Linux Shell, WebGUI and Physical Serial Console access. No confirmation is asked at deactivation time. Loosing access to these services device administrators are at risk of completely loosing device control.

Impact

For European organizations, particularly those operating critical telecommunications infrastructure or large-scale optical transport networks, this vulnerability poses a significant operational risk. Infinera G42 devices are often deployed in backbone networks, data centers, and service provider environments. If an administrator accidentally or maliciously disables all management interfaces, it could lead to prolonged outages or degraded network performance due to the inability to perform remote troubleshooting, configuration changes, or emergency interventions. This loss of availability could disrupt essential services, including internet connectivity, cloud services, and enterprise communications, impacting businesses and end-users. Recovery may require on-site physical access, which can be time-consuming and costly, especially for geographically dispersed or remote installations. Additionally, the lack of a confirmation step increases the risk of human error, which is a common cause of network incidents. While confidentiality and integrity are not directly impacted, the operational disruption and potential service downtime could have cascading effects on dependent systems and services across European networks.

CWE-1220Insufficient Granularity of Access Control (opens in a new tab)
Base weakness
The product implements access controls via a policy or other feature with the intention to disable or restrict accesses (reads and/or writes) to assets in a system from untrusted agents. However, implemented access controls lack required granularity, which renders the control policy too broad because it allows accesses from unauthorized agents to the security-sensitive assets.
Architecture and Design · Implementation · Testing
Access-control-policy protections must be reviewed for design inconsistency and common weaknesses.; Access-control-policy definition and programming flow must be tested in pre-silicon, post-silicon testing.
OWASP Cheat Sheets
Docker Security (opens in a new tab)
Third Party Javascript Management (opens in a new tab)
Virtual Patching (opens in a new tab)
OWASP ASVS 4.0.3
V1.4.4 (opens in a new tab)
V1.4.5 (opens in a new tab)
V1.10.1 (opens in a new tab)
Attack patterns
Accessing Functionality Not Properly Constrained by ACLs (opens in a new tab)
Exploiting Incorrectly Configured Access Control Security Levels (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 2 Jul 2025, 14:11 UTC

WeaknessesCWE-1220

Technical details

References

Community reviews

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