# CVE-2026-5448: 1-2 Byte Buffer Overflow in wolfSSL_X509_notAfter/notBefore

> A buffer overflow in wolfSSL's X.509 date parsing APIs allows attackers to execute code or cause denial of service via crafted certificates.

- **Severity:** Low 2.3 (`CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/U:Green`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 9 Apr 2026
- **Updated:** 10 Apr 2026
- **Also known as:** DEBIAN-CVE-2026-5448, GHSA-5jqq-xpcr-q3r7, JLSEC-2026-724, UBUNTU-CVE-2026-5448

## What is CVE-2026-5448?

CVE-2026-5448 is a low-severity memory corruption vulnerability in Wolfssl Wolfssl, published on 9 Apr 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

X.509 date buffer overflow in wolfSSL_X509_notAfter / wolfSSL_X509_notBefore. A buffer overflow may occur when parsing date fields from a crafted X.509 certificate via the compatibility layer API. This is only triggered when calling these two APIs directly from an application, and does not affect TLS or certificate verify operations in wolfSSL.

Weakness: CWE-122 (Heap-based Buffer Overflow)

## Which versions are affected by CVE-2026-5448?

It affects 1 product.


Products: Wolfssl Wolfssl.

## How do I fix CVE-2026-5448?

Apply the vendor's patch.

## Is CVE-2026-5448 being exploited?

There is no known exploitation of CVE-2026-5448 in the wild and no public exploit code.

## Other vulnerabilities in Wolfssl Wolfssl

- [CVE-2024-5991](https://insights.sbomify.com/CVE-2024-5991/): Buffer overread in domain name matching (critical 10.0)
- [CVE-2021-37155](https://insights.sbomify.com/CVE-2021-37155/): Security feature bypass in n/a (critical 9.8)
- [CVE-2020-36177](https://insights.sbomify.com/CVE-2020-36177/): Memory corruption in n/a (critical 9.8)
- [CVE-2014-2896](https://insights.sbomify.com/CVE-2014-2896/): Memory corruption in n/a (critical 9.8)
- [CVE-2014-2897](https://insights.sbomify.com/CVE-2014-2897/): Memory corruption in n/a (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-5448 and fix it if it is affected.

What it is: CVE-2026-5448 is a low-severity memory corruption vulnerability in Wolfssl Wolfssl, published on 9 Apr 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-5448 in the wild and no public exploit code.

Affected product: Wolfssl Wolfssl. 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-2026-5448/ (Markdown: https://insights.sbomify.com/CVE-2026-5448/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-5448
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-5448
- OSV: https://osv.dev/vulnerability/CVE-2026-5448

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-5448/
Summaries are generated and may contain mistakes; the official description above is the record.