# CVE-2026-59277: Spring Security InetAddressMatchers Incomplete Internal Network Classification

> Attackers can bypass internal network restrictions by exploiting incomplete IP classification logic in Spring Security's InetAddressMatchers utility.

- **Severity:** Low 3.7 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 27 Aug 2026
- **Updated:** 28 Aug 2026
- **Also known as:** CLEANSTART-2026-AI37690, GHSA-w9mx-mx4m-6m48

## What is CVE-2026-59277?

CVE-2026-59277 is a low-severity vulnerability in Spring Security, published on 27 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Spring Security's InetAddressMatchers utility provides matchInternal() and matchExternal() builders for constructing an InetAddressMatcher that classifies a given IP address as belonging to an internal (private) or external (public) network.
Spring Security 7.1.0

Weakness: CWE-693 (Protection Mechanism Failure)

## Which versions are affected by CVE-2026-59277?

It affects 1 product.


Products: Vmware Spring Security.

## How do I fix CVE-2026-59277?

Upgrade to a fixed version.

## Is CVE-2026-59277 being exploited?

There is no known exploitation of CVE-2026-59277 in the wild and no public exploit code.

## Other vulnerabilities in Spring Security

- [CVE-2014-3527](https://insights.sbomify.com/CVE-2014-3527/): Authorization Bypass in Spring Security (critical 9.8)
- [CVE-2026-59354](https://insights.sbomify.com/CVE-2026-59354/): Spring Security OAuth2 Authorization Server: Insufficient validation of Dynamic Client Registration metadata (critical 9.6)
- [CVE-2026-59270](https://insights.sbomify.com/CVE-2026-59270/): Spring Security embedded UnboundID LDAP server exposes well-known administrative bind DN on all network interfaces (critical 9.4)
- [CVE-2026-22732](https://insights.sbomify.com/CVE-2026-22732/): Under Some Conditions Spring Security HTTP Headers Are not Written (critical 9.1)
- [CVE-2023-34034](https://insights.sbomify.com/CVE-2023-34034/): Access Control Bypass in Spring Security (critical 9.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-59277 and fix it if it is affected.

What it is: CVE-2026-59277 is a low-severity vulnerability in Spring Security, published on 27 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-59277 in the wild and no public exploit code.

Affected product: Spring Security. 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-2026-59277/ (Markdown: https://insights.sbomify.com/CVE-2026-59277/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-59277
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-59277
- OSV: https://osv.dev/vulnerability/CVE-2026-59277

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-59277/
Summaries are generated and may contain mistakes; the official description above is the record.