CVE-2026-2537VulnerabilityPublished 16 Feb 2026Updated 23 Feb 2026

CVE-2026-2537: Comfast CF-E4 · Command Injection

Affects Comfast CF-E4Source CVE Database V5

Not known to be exploited · 27% EPSS · CVSS 5.1 Medium.

Data as of 25 Oct 2026, 19:02 UTC

CVSS 4.0 base score

5.1Medium

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

EPSS: 27.9% chance of exploitation in 30 days – higher than 98% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P

Base metrics

Attack Vector: Network
Attack Complexity: Low
Attack Requirements: None
Privileges Required: High
User Interaction: None
Vulnerable system confidentiality: Low
Vulnerable system integrity: Low
Vulnerable system availability: Low
Subsequent system confidentiality: None
Subsequent system integrity: None
Subsequent system availability: None

Threat metrics

Exploit Maturity: POC

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

Attack Vector: Network: The vulnerable system is bound to the network stack and the set of possible attackers extends beyond the other options listed below, 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: The attacker must take no measurable action to exploit the vulnerability. The attack requires no target-specific circumvention to exploit the vulnerability. An attacker can expect repeatable success against the vulnerable system.
Attack Requirements: None: The successful attack does not depend on the deployment and execution conditions of the vulnerable system. The attacker can expect to be able to reach the vulnerability and execute the exploit under all or most instances of the vulnerability.
Privileges Required: High: The attacker requires privileges that provide significant (e.g., administrative) control over the vulnerable system allowing full access to the vulnerable system’s settings and files.
User Interaction: None: The vulnerable system can be exploited without interaction from any human user, other than the attacker.
Vulnerable system confidentiality: Low: There is some loss of confidentiality. Access to some restricted information is obtained, but the attacker does not have control over what information is obtained, or the amount or kind of loss is limited. The information disclosure does not cause a direct, serious loss to the Vulnerable System.
Vulnerable system integrity: Low: Modification of data is possible, but the attacker does not have control over the consequence of a modification, or the amount of modification is limited. The data modification does not have a direct, serious impact to the Vulnerable System.
Vulnerable system availability: Low: Performance is reduced or there are interruptions in resource availability. Even if repeated exploitation of the vulnerability is possible, the attacker does not have the ability to completely deny service to legitimate users. The resources in the Vulnerable System are either partially available all of the time, or fully available only some of the time, but overall there is no direct, serious consequence to the Vulnerable System.
Subsequent system confidentiality: None: There is no loss of confidentiality within the Subsequent System or all confidentiality impact is constrained to the Vulnerable System.
Subsequent system integrity: None: There is no loss of integrity within the Subsequent System or all integrity impact is constrained to the Vulnerable System.
Subsequent system availability: None: There is no impact to availability within the Subsequent System or all availability impact is constrained to the Vulnerable System.
Exploit Maturity: POC: Based on threat intelligence sources each of the following must apply: · Proof-of-concept is publicly available · No knowledge of reported attempts to exploit this vulnerability · No knowledge of publicly available solutions used to simplify attempts to exploit the vulnerability

Definitions: FIRST CVSS v4.0 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 16 Feb 2026
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 2026-10-25.

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 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
ComfastCF-E4	Affected =2.6.0.1	Fixed in–

AI-suggested

Organizations should immediately audit Comfast CF-E4 devices to identify those running version 2.6.0.1 and restrict administrative access to trusted personnel and networks only. Change all default or weak credentials to strong, unique passwords to reduce the risk of unauthorized authentication. Implement network segmentation to isolate management interfaces from general user networks and the internet. Monitor device logs and network traffic for unusual activity indicative of exploitation attempts. If possible, disable or restrict access to the vulnerable /cgi-bin/mbox-config endpoint or the affected functionality until a vendor patch is released. Employ intrusion detection/prevention systems (IDS/IPS) with signatures targeting this vulnerability or related exploit attempts. Maintain an inventory of affected devices and stay alert for vendor updates or community-developed patches. Consider replacing or upgrading devices if no vendor support is forthcoming.

Description

A vulnerability was identified in Comfast CF-E4 2.6.0.1. This impacts an unknown function of the file /cgi-bin/mbox-config?method=SET&section=ntp_timezone of the component HTTP POST Request Handler. Such manipulation of the argument timestr leads to command injection. The attack may be launched remotely. The exploit is publicly available and might be used. The vendor was contacted early about this disclosure but did not respond in any way.

Impact

The primary impact of CVE-2026-2537 is the potential for attackers with authenticated access to execute arbitrary commands on Comfast CF-E4 devices remotely. This can lead to full device compromise, allowing attackers to alter configurations, disrupt network services, or use the device as a foothold for further attacks within an organization's network. Confidentiality may be breached if sensitive information stored or transmitted by the device is accessed or exfiltrated. Integrity is at risk as attackers can modify device settings or firmware. Availability could be impacted if the device is rendered inoperable or used in denial-of-service attacks. The requirement for authentication limits exposure to external unauthenticated attackers but does not eliminate risk, especially in environments with weak or default credentials. The lack of vendor response and patch availability increases the window of vulnerability, making timely mitigation critical for organizations relying on these devices.

Summary

CVE-2026-2537 is a command injection vulnerability identified in Comfast CF-E4 firmware version 2.6.0.1. The vulnerability resides in the HTTP POST request handler for the /cgi-bin/mbox-config endpoint, specifically when handling the 'timestr' argument within the 'ntp_timezone' section. Improper input validation allows an attacker to inject arbitrary OS commands through this parameter. The attack vector is remote and network-based, requiring the attacker to have high-level privileges (authentication) on the device. The vulnerability does not require user interaction and affects the confidentiality, integrity, and availability of the device by enabling arbitrary command execution. The CVSS v4.0 score is 5.1 (medium), reflecting the need for authentication and limited scope of impact. The device is typically used in networking environments, and exploitation could lead to device compromise, network disruption, or pivoting within internal networks.

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 23 Feb 2026, 21:18 UTC

Technical details

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