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External Control of File Name or Path in xDS SDS DataSource

Moderate
jrhee17 published GHSA-hgw6-8c77-v4gq Jun 18, 2026

Package

maven com.linecorp.armeria:armeria-xds (Maven)

Affected versions

<1.40.0

Patched versions

1.40.0

Description

External Control of File Name or Path in xDS SDS DataSource

Summary

DataSourceStream in the :xds module resolves control-plane-supplied filename and environment_variable fields from SDS Secret resources without any allow-list or base-directory confinement. A semi-trusted or compromised xDS control plane (or an attacker who can MITM SDS responses) can read arbitrary local files and environment variables on the xDS client host.

Affected component: xds/src/main/java/com/linecorp/armeria/xds/DataSourceStream.java
Introduced in: Armeria 1.38.0 (commit b199560b10, "Add support for SDS", #6597)
Affected versions: 1.38.0, 1.39.0

Impact

A semi-trusted or compromised xDS control plane (or an attacker who can inject/MITM SDS responses) can:

  • Read arbitrary files on the xDS client host — TLS private keys, /etc/passwd, mounted Kubernetes service-account tokens, cloud credential files, etc.
  • Read arbitrary environment variables — AWS_SECRET_ACCESS_KEY, CI tokens, database credentials, etc.

The read bytes are consumed as TLS key/cert/CA material. Combined with CWE-295 (silent disabling of upstream TLS peer verification), the exfiltrated secret can be presented to an attacker-chosen upstream, enabling data exfiltration. This is a confused-deputy / information-disclosure primitive driven entirely by control-plane-supplied configuration.

Severity: High — arbitrary host-level file and environment variable read via control-plane-pushed configuration.

Patches

TBD — not yet patched.

The fix should:

  1. Confine filename resolution to an operator-configured allow-list of base directories. After normalization, reject any path that escapes the allow-listed root.
  2. Gate environment_variable behind an explicit operator allow-list of permitted variable names.
  3. Default to denying both filename and environment_variable DataSources for control-plane-delivered (SDS) secrets unless explicitly enabled by the operator. This is stricter than upstream Envoy but appropriate when the control plane is not fully trusted.
  4. Document the trust model clearly so operators understand that enabling file/env DataSources grants the control plane host-level read capability.

Workarounds

  • Ensure the xDS control plane channel is authenticated and encrypted (mTLS) to prevent MITM injection of malicious SDS responses.
  • Run the xDS client with minimal filesystem permissions and a restricted environment to limit the blast radius of arbitrary reads.
  • If SDS file-based secrets are not needed, consider using inline DataSource bytes only (delivered over the SDS stream itself) and auditing control-plane configurations to ensure no filename or environment_variable DataSources are present.

References

Severity

Moderate

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 Network
Attack Complexity High
Attack Requirements None
Privileges Required High
User interaction None
Vulnerable System Impact Metrics
Confidentiality High
Integrity None
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:N/AC:H/AT:N/PR:H/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N

CVE ID

CVE-2026-11752

Weaknesses

External Control of File Name or Path

The product allows user input to control or influence paths or file names that are used in filesystem operations. Learn more on MITRE.

Credits