# CVE-2026-73631: Apache Struts: Shared parsing state in the JSON plugin

> Concurrent requests in Apache Struts JSON plugin may leak data across sessions if JSON parsing is enabled.

- **Severity:** Medium 4.3 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 15 Aug 2026
- **Updated:** 17 Aug 2026
- **Also known as:** GHSA-gvf6-rf7m-9h3g

## What is CVE-2026-73631?

CVE-2026-73631 is a medium-severity vulnerability in Apache Struts, published on 15 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Exposure of data element to wrong session vulnerability in the JSON plugin of Apache Struts. Per-request parsing state could be shared across concurrent requests, allowing data associated with one request to become observable in another, and configured parsing limits not to be enforced as intended. Populating actions from a JSON request body is not enabled by default; applications that do not use the JSON plugin are not affected.

This issue affects Apache Struts: 7.2.1.

Users are recommended to upgrade to version 7.3.0, which fixes the issue.

Weakness: CWE-567 (Unsynchronized Access to Shared Data in a Multithreaded Context)

## Which versions are affected by CVE-2026-73631?

It affects 1 product.


Products: Apache Struts.

## How do I fix CVE-2026-73631?

No fix has been published for CVE-2026-73631 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-73631 being exploited?

There is no known exploitation of CVE-2026-73631 in the wild and no public exploit code.

## Other vulnerabilities in Apache Struts

- [CVE-2020-17530](https://insights.sbomify.com/CVE-2020-17530/): Apache Struts Remote Code Execution (critical 9.8, exploited in the wild)
- [CVE-2017-9791](https://insights.sbomify.com/CVE-2017-9791/): Apache Struts 1 Improper Input Validation (critical 9.8, exploited in the wild)
- [CVE-2017-5638](https://insights.sbomify.com/CVE-2017-5638/): Apache Struts Remote Code Execution (critical 9.8, exploited in the wild)
- [CVE-2012-0391](https://insights.sbomify.com/CVE-2012-0391/): Apache Struts 2 Improper Input Validation (critical 9.8, exploited in the wild)
- [CVE-2018-11776](https://insights.sbomify.com/CVE-2018-11776/): Apache Struts Remote Code Execution (high 8.1, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-73631 and fix it if it is affected.

What it is: CVE-2026-73631 is a medium-severity vulnerability in Apache Struts, published on 15 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-73631 in the wild and no public exploit code.

Affected product: Apache Struts. 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-2026-73631/ (Markdown: https://insights.sbomify.com/CVE-2026-73631/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-73631
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-73631
- OSV: https://osv.dev/vulnerability/CVE-2026-73631

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-73631/
Summaries are generated and may contain mistakes; the official description above is the record.