Security readout for executives and security teams
Plain-English summary
Yamcs before 5.12.7 can let a highly privileged authenticated user turn editable mission database Python algorithms into code execution on the Yamcs host. This is critical where Yamcs supports mission operations, because compromise could affect confidentiality, integrity, and availability of the control environment.
Executive priority
Prioritize remediation for any production or mission-connected Yamcs instance. The privilege requirement lowers broad internet-scale risk, but a compromised or malicious privileged account could lead to full host compromise and operational disruption.
Technical view
The vulnerable Python algorithm evaluation path used Jython via JSR-223 to dynamically compile user-controlled algorithm text without a secure sandbox. An authenticated user with ChangeMissionDatabase could replace algorithm logic through the REST API and execute Java-backed code on the underlying host. Fixed releases disable algorithm editing by default.
Likely exposure
Exposure is limited to Yamcs deployments before 5.12.7 where authenticated users can exercise ChangeMissionDatabase and edit Python algorithms. No CPEs were provided in the source bundle, so asset discovery should rely on Yamcs version and configuration.
Exploitation context
The sources describe authenticated remote code execution with high privileges required. The CVE is not listed as KEV in the bundle, and no cited source here confirms active exploitation. Treat as urgent because exploitation would cross from application control into host execution.
Researcher notes
This is CWE-94 code injection in Yamcs algorithm evaluation. The key conditions are pre-5.12.7 code, Python algorithms, REST-based mission database modification, and ChangeMissionDatabase privilege. Evidence is strong for affected range and fixes, but the bundle does not prove exploitation in the wild.
Mitigation direction
- Upgrade Yamcs to 5.12.7 or 5.13.0.
- Confirm algorithm editing is disabled unless explicitly required.
- Restrict ChangeMissionDatabase to a minimal trusted administrator group.
- Review vendor advisory and release notes for deployment-specific guidance.
- Increase monitoring around mission database and algorithm changes.
Validation and detection
- Inventory all Yamcs deployments and record exact versions.
- Identify users and roles with ChangeMissionDatabase privilege.
- Check whether Python algorithm editing is enabled in each environment.
- Review audit logs for recent mission database algorithm changes.
- Verify upgraded instances are running 5.12.7, 5.13.0, or later.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-94: Code execution behavior lookup
Code execution and unsafe deserialization weaknesses often justify reviewing execution behavior and process telemetry. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupDatabase behavior lookup
The CVE wording references database injection or access, so collection and exfiltration review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2026-46621 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Critical
- CVSS
- 9.1 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
SSVC decision data
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H2.36GitHub_MVulnerability scoring details
Base CVSS 3.1 score
9.1CriticalVector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/yamcs/yamcs/security/advisories/GHSA-2g95-6x5q-xjwjCVE reference, GitHub_M · x_refsource_CONFIRM
- https://github.com/yamcs/yamcs/commit/3c550348f866af4675d2ba4a51d8d12b7c7c6011CVE reference, GitHub_M · x_refsource_MISC
- https://github.com/yamcs/yamcs/commit/4ff8fda642ea8c3309a4d3f379aa77b763148992CVE reference, GitHub_M · x_refsource_MISC
- https://github.com/yamcs/yamcs/releases/tag/yamcs-5.12.7CVE reference, GitHub_M · x_refsource_MISC
- https://github.com/yamcs/yamcs/releases/tag/yamcs-5.13.0CVE reference, GitHub_M · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Control of Generation of Code ('Code Injection')
Improper Control of Generation of Code ('Code Injection') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.