Answer in brief
CVE-2026-62847 records a High severity (CVSS 8.2) vulnerability in Metalama: Local code execution via DLL planting in world-writable temporary directories (Linux/macOS). The current sources do not mark it as known exploited. The current feed maps metalama/Metalama (generic), Metalama.Framework (nuget), Metalama.Framework (nuget), Metalama.Framework (nuget) and additional mapped packages. Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 8.2. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps metalama/Metalama (generic), Metalama.Framework (nuget), Metalama.Framework (nuget), Metalama.Framework (nuget) and additional mapped packages. Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| metalama/Metalamageneric | <2025.1.18 || >=2025.2.0-preview <=2025.2.5-rc || >=2026.0.0-preview <2026.0.25 || >=2026.1.0-preview <2026.1.19 | 2025.1.18, 2026.0.25, 2026.1.19 |
| Metalama.Frameworknuget | >=2026.1.0-preview,<2026.1.19 | 2026.1.19 |
| Metalama.Frameworknuget | <2025.1.18 | 2025.1.18 |
| Metalama.Frameworknuget | >=2026.0.0-preview,<2026.0.25 | 2026.0.25 |
| Metalama.Toolnuget | >=2026.1.0-preview,<2026.1.19 | 2026.1.19 |
| Metalama.Toolnuget | <2025.1.18 | 2025.1.18 |
| Metalama.Toolnuget | >=2026.0.0-preview,<2026.0.25 | 2026.0.25 |
Published upstream
Oct 30, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 30, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Oct 14, 2026
Metalama is a Roslyn-based open-source patterns and architecture toolkit for C#. Prior to 2025.1.18, 2026.0.25 and 2026.1.19, Metalama.Framework and Metalama.Tool load and execute compile-time assemblies, auxiliary executable tools and embedded helper assemblies from predictable temporary directories. On `Linux` and `macOS`, the default `Path.GetTempPath()` location is world-writable, and existing artifacts are trusted based on sentinel or `.completed` marker files rather than integrity verification. A local unprivileged user on a shared machine or CI/build agent can pre-create the deterministic directory structure and plant a malicious DLL with the matching sentinel. When a higher-privileged developer or build account subsequently builds, Metalama skips regeneration and executes the planted artifact in the compiler, IDE or MSBuild process as the building user. This permits cross-user privilege escalation, reading source and secrets, supply-chain tampering with build output, or disrupting builds. Default Windows per-user temporary directories are protected by ACLs and are not affected. Deployer-selected insecure cache locations are outside the vulnerability's scope. This issue is fixed in versions 2025.1.18, 2026.0.25 and 2026.1.19.
Quoted source text, attributed separately from HOL analysis.