CVE-2026-123373tmatens compose-lint link following
CVE-2026-123373 is a link following in tmatens compose-lint, rated low (2.3 on CVSS 4.0).
Why this priority: Low severity, with no exploitation signal.
Published · Updated · NVD status: Received
What it is
The software follows a symbolic link an attacker planted, so it reads or writes a file other than the one it checked. Error messages reveal internal details useful to an attacker.
How it is reached
An attacker can exploit it over the network, without an account, but someone has to act first, such as opening a file or following a link. Success also depends on conditions the attacker does not fully control.
What an attacker gains
The direct impact is limited: partial access to data or a partial outage. In practice, this kind of flaw lets an attacker read or write files outside the folders the service meant to expose.
Is it being exploited?
There is no public report of exploitation yet.
What to do
- Upgrade tmatens compose-lint to 0.25.0 or later.
- Until it is patched, keep it off the internet or behind a VPN, allowlist or authenticating proxy.
- Warn the people who use it, and filter files and links on the way in.
Description from NVD
compose-lint is a Docker Compose security linter that identifies dangerous misconfigurations before deployment. From 0.2.0 until 0.25.0, compose-lint follows a project-controlled symbolic link used as the Compose file outside the project. The same issue affects compose.override.yml and a COMPOSE_FILE entry from 0.22.0, and an env_file target from 0.23.0. If an external Compose-related target fails YAML parsing, the error quotes an attacker-uncontrolled line into standard error, JSON errors, and SARIF notifications, while an external env_file can expose credential-like key names through CL-0020 and CL-0021 findings. The attacker selects the target path but not the exact parser-failure line, values from env_file are not printed, and the pass or fail result is unchanged. This issue is fixed in version 0.25.0.
What this means for your architecture.
A CVE names a product. Whether it matters depends on where that product sits in your systems: what reaches it, which trust boundary it guards and what it can reach once compromised. Veriom maps your components, their relationships and your trust boundaries from your code, cloud and delivery evidence, so you can see where a component like this sits. The radar itself does not look at your systems.
Components it touches
- File storage the service can read or write. The flaw sits between the application and the file system it can reach.
- Error responses, logs and debug endpoints. The flaw sits between internal data and whoever can read the response or log.
- APIs that over-share. The flaw sits between internal data and whoever can read the response or log.
Trust boundaries in play
- Internet-facing entry points. No account is needed. Any instance reachable from outside your perimeter, through a load balancer, gateway, VPN or exposed admin port, is in scope.
- People who open files and links. Mail, chat and browsers are the delivery path.
- Between the application and the file system it can reach. An attacker who crosses it can read or write files outside the folders the service meant to expose.
- Between internal data and whoever can read the response or log. An attacker who crosses it can learn data or internals that help a follow-up attack.
Questions to answer about your own systems
- Where does tmatens compose-lint run in your systems, and at which version?
- Which of those instances can be reached from the internet or partner networks?
- What can it reach once compromised: which data stores, secrets and services?
Sources
- CVE records and CVSS scores from the NVD CVE API. This product uses the NVD API but is not endorsed or certified by the NVD.
- Exploitation status from CISA’s Known Exploited Vulnerabilities catalog.
- Exploit likelihood from FIRST’s Exploit Prediction Scoring System (EPSS), refreshed daily.
- Explanations are written by Veriom from fixed templates over each record’s data, not by a person reviewing each CVE. Descriptions are quoted from the records as published.