Visitar URL original
`gh codespace ports forward` exposes forwarded services on all network interfaces by default · Advisory · cli/cli · GitHub
Skip to content

Repository navigation

`gh codespace ports forward` exposes forwarded services on all network interfaces by default

Low
BagToad published GHSA-vfhh-p7hm-pxfh Aug 20, 2026

Package

gomod github.com/cli/cli/v2 (Go)

Affected versions

>=v2.28.0

Patched versions

v2.98.0

Description

Summary

A security vulnerability has been identified in GitHub CLI where gh codespace ports forward binds the local forwarded port to all available network interfaces by default. While port forwarding is active, a service in a Codespace can therefore become reachable through the user's non-loopback local IP addresses by other hosts that can route to the user's machine.

This behavior does not change the GitHub-side visibility of the Codespaces port. Instead, it exposes the forwarded service through a wildcard-bound listener on the user's local machine, even when the source Codespaces port remains private.

Details

When a user runs:

gh codespace ports forward <remote-port>:<local-port>

GitHub CLI creates a local TCP listener for the requested local port. In affected versions, that listener binds to the wildcard address, which accepts connections through every available network interface.

For example, forwarding a private Codespaces service to local port 18000 can result in a listener equivalent to:

*:18000

A host on the same LAN, VPN, or another network that can route to the user's machine may connect to that listener while the forwarding command is running. The attacker does not need shell access to the user's machine, access to locally stored credentials, or access to the Codespace.

The vulnerability was introduced in GitHub CLI v2.28.0.

In v2.98.0, gh codespace ports forward binds to the loopback interface by default. Users who intentionally need to expose a forwarded service through other local network interfaces can opt into the previous behavior with the new --all-interfaces flag.

The command also reports the actual local listener address so users can confirm whether forwarding is limited to loopback or exposed through all interfaces.

Impact

A network-adjacent attacker can access a service forwarded by gh codespace ports forward through the victim machine's non-loopback network interfaces while the forwarding process is active.

The precise impact depends on the forwarded service. At minimum, this creates unintended network exposure. If the service provides sensitive information or state-changing operations without additional authentication, an attacker may be able to read that information or invoke those operations.

Successful exploitation requires the victim to be actively forwarding a port and the attacker to be able to route traffic to the victim's machine.

Remediation and Mitigation

  1. Upgrade GitHub CLI to v2.98.0 or later.
  2. On affected versions, avoid gh codespace ports forward on untrusted or shared networks.
  3. Use host firewall rules to block inbound access to locally forwarded ports.
  4. Stop the forwarding process when it is no longer needed.

Severity

Low

CVSS overall score

This score calculates overall vulnerability severity from 0 to 10 and is based on the Common Vulnerability Scoring System (CVSS).
/ 10

CVSS v4 base metrics

Exploitability Metrics
Attack Vector Adjacent
Attack Complexity Low
Attack Requirements Present
Privileges Required Low
User interaction None
Vulnerable System Impact Metrics
Confidentiality Low
Integrity Low
Availability None
Subsequent System Impact Metrics
Confidentiality None
Integrity None
Availability None

CVSS v4 base metrics

Exploitability Metrics
Attack Vector: This metric reflects the context by which vulnerability exploitation is possible. This metric value (and consequently the resulting severity) will be larger the more remote (logically, and physically) an attacker can be in order to exploit the vulnerable system. The assumption is that the number of potential attackers for a vulnerability that could be exploited from across a network is larger than the number of potential attackers that could exploit a vulnerability requiring physical access to a device, and therefore warrants a greater severity.
Attack Complexity: This metric captures measurable actions that must be taken by the attacker to actively evade or circumvent existing built-in security-enhancing conditions in order to obtain a working exploit. These are conditions whose primary purpose is to increase security and/or increase exploit engineering complexity. A vulnerability exploitable without a target-specific variable has a lower complexity than a vulnerability that would require non-trivial customization. This metric is meant to capture security mechanisms utilized by the vulnerable system.
Attack Requirements: This metric captures the prerequisite deployment and execution conditions or variables of the vulnerable system that enable the attack. These differ from security-enhancing techniques/technologies (ref Attack Complexity) as the primary purpose of these conditions is not to explicitly mitigate attacks, but rather, emerge naturally as a consequence of the deployment and execution of the vulnerable system.
Privileges Required: This metric describes the level of privileges an attacker must possess prior to successfully exploiting the vulnerability. The method by which the attacker obtains privileged credentials prior to the attack (e.g., free trial accounts), is outside the scope of this metric. Generally, self-service provisioned accounts do not constitute a privilege requirement if the attacker can grant themselves privileges as part of the attack.
User interaction: This metric captures the requirement for a human user, other than the attacker, to participate in the successful compromise of the vulnerable system. This metric determines whether the vulnerability can be exploited solely at the will of the attacker, or whether a separate user (or user-initiated process) must participate in some manner.
Vulnerable System Impact Metrics
Confidentiality: This metric measures the impact to the confidentiality of the information managed by the VULNERABLE SYSTEM due to a successfully exploited vulnerability. Confidentiality refers to limiting information access and disclosure to only authorized users, as well as preventing access by, or disclosure to, unauthorized ones.
Integrity: This metric measures the impact to integrity of a successfully exploited vulnerability. Integrity refers to the trustworthiness and veracity of information. Integrity of the VULNERABLE SYSTEM is impacted when an attacker makes unauthorized modification of system data. Integrity is also impacted when a system user can repudiate critical actions taken in the context of the system (e.g. due to insufficient logging).
Availability: This metric measures the impact to the availability of the VULNERABLE SYSTEM resulting from a successfully exploited vulnerability. While the Confidentiality and Integrity impact metrics apply to the loss of confidentiality or integrity of data (e.g., information, files) used by the system, this metric refers to the loss of availability of the impacted system itself, such as a networked service (e.g., web, database, email). Since availability refers to the accessibility of information resources, attacks that consume network bandwidth, processor cycles, or disk space all impact the availability of a system.
Subsequent System Impact Metrics
Confidentiality: This metric measures the impact to the confidentiality of the information managed by the SUBSEQUENT SYSTEM due to a successfully exploited vulnerability. Confidentiality refers to limiting information access and disclosure to only authorized users, as well as preventing access by, or disclosure to, unauthorized ones.
Integrity: This metric measures the impact to integrity of a successfully exploited vulnerability. Integrity refers to the trustworthiness and veracity of information. Integrity of the SUBSEQUENT SYSTEM is impacted when an attacker makes unauthorized modification of system data. Integrity is also impacted when a system user can repudiate critical actions taken in the context of the system (e.g. due to insufficient logging).
Availability: This metric measures the impact to the availability of the SUBSEQUENT SYSTEM resulting from a successfully exploited vulnerability. While the Confidentiality and Integrity impact metrics apply to the loss of confidentiality or integrity of data (e.g., information, files) used by the system, this metric refers to the loss of availability of the impacted system itself, such as a networked service (e.g., web, database, email). Since availability refers to the accessibility of information resources, attacks that consume network bandwidth, processor cycles, or disk space all impact the availability of a system.
CVSS:4.0/AV:A/AC:L/AT:P/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N

CVE ID

CVE-2026-72924

Weaknesses

No CWEs

Credits