# CVE-2026-81895: SQL injection in Concrete CMS

> Authenticated users can inject SQL via Document Library block configuration, leading to data exposure or modification when pages are rendered.

- **Severity:** High 8.5 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 15 Sep 2026
- **Updated:** 22 Sep 2026
- **Also known as:** GHSA-rc56-pff2-6crm

## What is CVE-2026-81895?

CVE-2026-81895 is a high-severity SQL injection vulnerability in Concretecms Concrete Cms, published on 15 Sep 2026. An attacker needs administrator access to exploit it, and only if a user opens a file or follows a link.

### Official description

In Concrete CMS before 9.5.3, the Document Library block stored the file-set identifiers submitted through fsID[] without validating them as integers, and when the block was configured with setMode set to any it concatenated each stored identifier directly into the file-set filter query instead of casting it or binding it as a parameter. An authenticated user permitted to add or edit a Document Library block could therefore persist SQL syntax in the block configuration (btDocumentLibrary.setIds), and that stored expression was executed every time the published page containing the block was rendered, producing stored, time-based blind SQL injection. The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 8.5 with vector CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N. Thanks Habib Allah for reporting.

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

## Which versions are affected by CVE-2026-81895?

It affects 1 product.


Products: Concretecms Concrete Cms.

## How do I fix CVE-2026-81895?

No fix has been published for CVE-2026-81895 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-81895 being exploited?

There is no known exploitation of CVE-2026-81895 in the wild and no public exploit code.

## Other vulnerabilities in Concretecms Concrete Cms

- [CVE-2023-48648](https://insights.sbomify.com/CVE-2023-48648/): Concrete CMS allows unauthorized access because directories can be created with insecure permissions (critical 9.8)
- [CVE-2022-21829](https://insights.sbomify.com/CVE-2022-21829/): Code injection in concrete CMS (critical 9.8)
- [CVE-2021-22958](https://insights.sbomify.com/CVE-2021-22958/): Server-Side Request Forgery vulnerability in concrete5 (critical 9.8)
- [CVE-2021-40098](https://insights.sbomify.com/CVE-2021-40098/): Path traversal in n/a (critical 9.8)
- [CVE-2026-8134](https://insights.sbomify.com/CVE-2026-8134/): Concrete CMS Vulnerable to Relative Path Traversal (critical 9.4)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-81895 and fix it if it is affected.

What it is: CVE-2026-81895 is a high-severity SQL injection vulnerability in Concretecms Concrete Cms, published on 15 Sep 2026. An attacker needs administrator access to exploit it, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-81895 in the wild and no public exploit code.

Affected product: Concretecms Concrete Cms. No package-level version data is available, so check the vendor advisory linked from the reference page.

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-2026-81895/ (Markdown: https://insights.sbomify.com/CVE-2026-81895/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-81895
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-81895
- OSV: https://osv.dev/vulnerability/CVE-2026-81895

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From sbomify Insights: https://insights.sbomify.com/CVE-2026-81895/
Summaries are generated and may contain mistakes; the official description above is the record.