# CVE-2026-75513: Marten: SQL injection in Marten's LINQ provider via unescaped string literals

> Attackers can inject SQL via LINQ filters to bypass authorization and exfiltrate or modify data in Marten-based applications.

- **Severity:** Critical 9.1 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 16 Sep 2026
- **Updated:** 19 Sep 2026
- **Also known as:** GHSA-rfx3-98h7-v3xp

## What is CVE-2026-75513?

CVE-2026-75513 is a critical SQL injection vulnerability in JasperFx marten, published on 16 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Marten is a .NET Transactional Document DB and Event Store on PostgreSQL. From version 7.0.0 until 9.13.0, several Marten LINQ and tenant-management paths interpolate runtime, potentially attacker-controlled strings into single-quoted SQL literals without escaping or parameterization. The primary confirmed vector is a dictionary indexer key used by Where filters in src/Marten/Linq/Members/Dictionaries/DictionaryItemMember.cs. Additional affected sinks include SelectParser.cs, DatabaseScopedTenantPartitions.cs, and DeleteAllForTenant.cs reached through IEventStore.DeleteProjectionProgressAsync, while DictionaryContainsKeyFilter.cs (Newtonsoft serializer only; System.Text.Json is not affected) handles ContainsKey calls. Events/Daemon/Internals/EventLoader.cs contains a related per-tenant partition-pruning literal that the advisory identifies as a defense-in-depth sink. A crafted single quote can escape the generated literal, enabling filter or multi-tenant authorization bypass and blind data exfiltration, and deployments that permit semicolon-batched Npgsql statements may also allow data modification. This issue is fixed in version 9.13.0.

Weakness: CWE-89 (Improper Neutralization of Special Elements used in an SQL Command)

## Which versions are affected by CVE-2026-75513?

2 open source packages ship an affected version, including Marten.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `Marten` | NuGet | From 7.0.0 | 9.13.0 |
| `Marten` | NuGet | From 7.0.0 | 9.13.0 |

## How do I fix CVE-2026-75513?

Upgrade Marten to 9.13.0 or later.

## Is CVE-2026-75513 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-75513 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-75513 and fix it if it is affected.

What it is: CVE-2026-75513 is a critical SQL injection vulnerability in JasperFx marten, published on 16 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-75513 exists.

Affected packages and fixed versions:
- Marten (NuGet): affected from 7.0.0; fixed in 9.13.0
- Marten (NuGet): affected from 7.0.0; fixed in 9.13.0

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-75513/ (Markdown: https://insights.sbomify.com/CVE-2026-75513/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-75513
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-75513
- OSV: https://osv.dev/vulnerability/CVE-2026-75513

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-75513/
Summaries are generated and may contain mistakes; the official description above is the record.