# CVE-2026-55565: Yamcs remote code execution via unescaped StreamSQL LIKE pattern

Source: https://junglewise.ai/threats/cve-2026-55565-yamcs-remote-code-execution-via-unescaped-streamsql-like-pattern  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-28. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-55565 · Severity: critical · CVSS 9.9 · Published 2026-08-28

Yamcs is a telemetry and command processing system used in aerospace and satellite operations. A flaw in the StreamSQL query compiler allows authenticated users with routine read-only access (such as permission to view events or table data) to inject arbitrary Java code that executes with the privileges of the Yamcs process. An attacker can achieve complete system compromise, including tampering with telemetry, suppressing commands, accessing credentials, and establishing persistence.

Technologies: [org.yamcs:yamcs-core (Maven)](https://junglewise.ai/threats/technologies/org-yamcs-yamcs-core). Vendors: [Maven](https://junglewise.ai/threats/vendors/maven).

## Quick answers

**Is CVE-2026-55565 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-55565 being exploited in the wild.

**How severe is CVE-2026-55565?** Critical severity, with a CVSS score of 9.9, published 28 August 2026.

**Which products and versions are affected?** org.yamcs:yamcs-core (Maven) ECOSYSTEM:introduced=5.13.0,fixed=5.13.2; Space Applications Services Yamcs Core 5.13.0 through 5.13.1, 5.12.7 and earlier.

**Is there a fix for CVE-2026-55565?** Yes. org.yamcs:yamcs-core (Maven): upgrade to 5.13.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-55565 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-55565?** Check whether you run org.yamcs:yamcs-core (Maven) or Space Applications Services Yamcs Core at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- org.yamcs:yamcs-core (Maven): upgrade to 5.13.2 or later

  ```sh
  # set org.yamcs:yamcs-core to 5.13.2 in your pom.xml or build.gradle
  ```


## Technical details

The vulnerability is a code injection flaw in the StreamSQL compiler. The `LikeExpression#fillCode_getValueReturn` method appends user-controlled LIKE patterns directly into generated Java string literals without escaping, whereas the sibling `ValueExpression` class correctly escapes via `escapeJavaString()`. When a pattern contains a double-quote character, it breaks out of the string literal and injects arbitrary Java code—for example, a `static{}` block that invokes `ProcessBuilder` to execute OS commands. This code is compiled with Janino and instantiated at stream preparation time, before any data flows. The vulnerability is reachable via four different API endpoints: `executeSql` and `streamSql` (requiring `ControlArchiving` privilege), `readRows` (requiring `ReadTables`), events queries and exports (requiring `ReadEvents`), and activities listings (requiring `ReadActivities`). All three lower-privilege paths are verified exploitable. No SecurityManager or Janino sandbox constraints are configured, so compiled code can freely call `Runtime` and `ProcessBuilder`. Patches are available in versions 5.12.8 and 5.13.2.

## Affected products

- Yamcs yamcs-core 5.13.0 through 5.13.1, 5.12.7 and earlier

## Identifiers

- CVE-2026-55565
- GHSA-c64q-hj4j-375f

## Timeline

- 2026-08-28: disclosed: GitHub Security Advisory published
- 2026: patched: Versions 5.12.8 and 5.13.2 released with fix

## References

- [https://api.github.com/users/Marnick39](https://api.github.com/users/Marnick39)
- [https://github.com/Marnick39](https://github.com/Marnick39)
- [https://api.github.com/users/Marnick39/gists%7B/gist_id%7D](https://api.github.com/users/Marnick39/gists%7B/gist_id%7D)
- [https://api.github.com/users/Marnick39/repos](https://api.github.com/users/Marnick39/repos)
- [https://avatars.githubusercontent.com/u/17315511?v=4](https://avatars.githubusercontent.com/u/17315511?v=4)
- [https://api.github.com/users/Marnick39/events%7B/privacy%7D](https://api.github.com/users/Marnick39/events%7B/privacy%7D)

## Related threats

- [Yamcs DOM XSS in Extension Routing](https://junglewise.ai/threats/cve-2026-55566-yamcs-dom-xss-in-extension-routing)
- [Yamcs remote code execution via YAML injection in instance template](https://junglewise.ai/threats/cve-2026-55559-yamcs-remote-code-execution-via-yaml-injection-in-instance)
- [Yamcs unauthenticated directory traversal](https://junglewise.ai/threats/cve-2026-55552-yamcs-unauthenticated-directory-traversal)
- [Yamcs reflected XSS in authorize endpoint](https://junglewise.ai/threats/cve-2026-55549-yamcs-reflected-xss-in-authorize-endpoint)
- [Yamcs missing authorization on role and privilege enumeration endpoints](https://junglewise.ai/threats/cve-2026-55547-yamcs-missing-authorization-on-role-and-privilege-enumeration)