---
title: "CVE-2026-75513: Marten's LINQ provider has SQL injection via unescaped string literals"
url: https://erroneo.us/security/cve/CVE-2026-75513/
description: "CVE-2026-75513 (Marten (NuGet)): Marten is a .NET Transactional Document DB and Event Store on PostgreSQL. From version 7.0.0 until 9.13.0, several Marten…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-09-16
date_modified: 2026-09-19
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-75513"
kev: false
cvss: 9.1
epss: 0.00468
license: All rights reserved. Quote with attribution and a link.
---

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

**Signal:** Critical, preconditions apply. Severe if exploited, but exploitation needs conditions that may not apply to you. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- Not in CISA KEV , but CISA’s SSVC assessment records a public proof-of-concept, so attack code exists.
- EPSS 0.5% , percentile 39: FIRST’s model estimates a 0.5% chance of exploitation activity in the next 30 days, higher than 39% of all scored CVEs (low). EPSS is a probability, not a verdict.
- Needs an account (low (any account)). Exposure depends on who can log in.
- Only applies if your dependency tree includes Marten (NuGet) >= 7.0.0, <= 9.12.0, fixed in 9.13.0 . Check your lockfile, including transitive dependencies.

## What it is

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.

## Affected packages

- NuGet `Marten` >= 7.0.0, <= 9.12.0 → fixed: 9.13.0

## Affected products (CVE record)

- JasperFx marten: >= 7.0.0, < 9.13.0

## Severity

- GitHub_M CVSS 3.1: 9.1 `CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:L`
- GitHub CVSS 3.1: 9.1 `CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:L`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation poc , automatable no , technical impact partial .
- FIRST EPSS (model of 2026-10-21): 0.47% probability of exploitation activity in the next 30 days; percentile 39.

## Sources

- [GitHub Advisory GHSA-rfx3-98h7-v3xp](https://github.com/advisories/GHSA-rfx3-98h7-v3xp)
- [CVE.org record CVE-2026-75513](https://www.cve.org/CVERecord?id=CVE-2026-75513)
- [NVD entry CVE-2026-75513](https://nvd.nist.gov/vuln/detail/CVE-2026-75513)
- [github.com](https://github.com/JasperFx/marten/security/advisories/GHSA-rfx3-98h7-v3xp)
- [github.com](https://github.com/JasperFx/marten/pull/4911)
- [github.com](https://github.com/JasperFx/marten/commit/61882d0424854cb48703f08bdb246894ac576bed)
- [github.com](https://github.com/JasperFx/marten/releases/tag/9.13.0)

---
Source page: https://erroneo.us/security/cve/CVE-2026-75513/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt