# CVE-2026-95616: Apache WSS4J: Unauthenticated denial of service via integer overflow in DER parsing of X.509 certificate extensions

> Unauthenticated attackers can cause denial of service via memory exhaustion by sending crafted X.509 certificates with oversized extension lengths.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 30 Sep 2026
- **Updated:** 30 Sep 2026
- **Also known as:** DEBIAN-CVE-2026-95616, GHSA-9gjf-54jg-6353, UBUNTU-CVE-2026-95616

## What is CVE-2026-95616?

CVE-2026-95616 is a high-severity vulnerability in Apache WSS4J, published on 30 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

An integer overflow in WSS4J's DER bounds check lets an oversized allocation pass validation. An unauthenticated attacker can send a SOAP message carrying an X.509 certificate whose SubjectKeyIdentifier extension declares a length of 0x7FFFFFFF; WSS4J decodes this while resolving the signature's key reference, before the message is authenticated, so an eleven-byte extension triggers a 2 GB allocation. Repeated requests exhaust server memory.
Users are recommended to upgrade to versions 4.0.2 or 3.0.6 or 2.4.4, which fix this issue.

Weakness: CWE-190 (Integer Overflow or Wraparound)

## Which versions are affected by CVE-2026-95616?

It affects 1 product.


Products: Apache Wss4j.

## How do I fix CVE-2026-95616?

No fix has been published for CVE-2026-95616 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-95616 being exploited?

There is no known exploitation of CVE-2026-95616 in the wild and no public exploit code.

## Other vulnerabilities in Apache WSS4J

- [CVE-2026-88920](https://insights.sbomify.com/CVE-2026-88920/): Apache WSS4J: SAML Sender-Vouches Authentication Bypass (critical 9.8)
- [CVE-2026-87830](https://insights.sbomify.com/CVE-2026-87830/): Apache WSS4J: Streaming WS-SecurityPolicy validation may skip element-protection checks. (critical 9.1)
- [CVE-2026-89238](https://insights.sbomify.com/CVE-2026-89238/): Apache WSS4J: WSS4J EncryptedHeader child confusion causing wrong protected-header selection (critical 9.1)
- [CVE-2026-85532](https://insights.sbomify.com/CVE-2026-85532/): Apache WSS4J: Insufficient Validation of Derived-Key Parameters (high 7.5)
- [CVE-2026-92121](https://insights.sbomify.com/CVE-2026-92121/): Apache WSS4J: WS-SecurityPolicy signature checks skipped in the streaming code after an STR-Transform reference (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-95616 and fix it if it is affected.

What it is: CVE-2026-95616 is a high-severity vulnerability in Apache WSS4J, published on 30 Sep 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-2026-95616 in the wild and no public exploit code.

Affected product: Apache WSS4J. 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-2026-95616/ (Markdown: https://insights.sbomify.com/CVE-2026-95616/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-95616
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-95616
- OSV: https://osv.dev/vulnerability/CVE-2026-95616

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-95616/
Summaries are generated and may contain mistakes; the official description above is the record.