---
title: "CVE-2026-3548\n    | Ubuntu"
description: Ubuntu is an open source software operating system that runs from the
  desktop, to the cloud, to all your internet connected things.
url: https://ubuntu.com/security/CVE-2026-3548?format=md
keywords: index, follow
---

# CVE-2026-3548

Publication date 19 March 2026

Last updated 10 July 2026

---

Ubuntu priority

**Medium**

[Why this priority?](https://ubuntu.com/security/cves/about#priority )

## Cvss 3 Severity Score

**9.8 · Critical**

[Score breakdown](https://ubuntu.com/security/CVE-2026-3548?format=md#impact-score)

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## Description

Two buffer overflow vulnerabilities existed in the wolfSSL CRL parser when
parsing CRL numbers: a heap-based buffer overflow could occur when
improperly storing the CRL number as a hexadecimal string, and a
stack-based overflow for sufficiently sized CRL numbers. With appropriately
crafted CRLs, either of these out of bound writes could be triggered. Note
this only affects builds that specifically enable CRL support, and the user
would need to load a CRL from an untrusted source.

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| wolfssl | 26.04 LTS resolute | Needs evaluation |
| 25.10 questing | Ignored end of life, was needs-triage |
| 24.04 LTS noble | Needs evaluation |
| 22.04 LTS jammy | Needs evaluation |
| 20.04 LTS focal | Needs evaluation |
| 18.04 LTS bionic | Needs evaluation |
| 16.04 LTS xenial | Needs evaluation |

---

* [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)
* [What do statuses mean?](https://ubuntu.com/security/cves/about#statuses)

## Severity score breakdown

CVSS version:

CVSS v4.0

[CVSS v4.0](https://ubuntu.com/security/CVE-2026-3548?format=md)
[CVSS v3.0](https://ubuntu.com/security/CVE-2026-3548?format=md)

**Base score**

7.2 · High

* Base metrics

  | Parameter | Value |
  | --- | --- |
  | Attack vector | Network |
  | Attack complexity | Low |
  | Attack requirements | Present |
  | Privileges required | None |
  | User interaction | None |
  | Vulnerable system - Confidentiality impact | High |
  | Vulnerable system - Integrity impact | High |
  | Vulnerable system - Availability impact | High |
  | Subsequent system - Confidentiality impact | None |
  | Subsequent system - Integrity impact | None |
  | Subsequent system - Availability impact | None |
* Scores

  | Parameter | Value |
  | --- | --- |
  | Base score | 7.2 · High |
  | Base + Threat score | - |
  | Base + Environmental score | - |
  | Base + Threat + Environmental score | - |

**Vector:** CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-3548)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2026-3548)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2026-3548)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2026-3548)

### Other references

* <https://www.cve.org/CVERecord?id=CVE-2026-3548>
* <https://github.com/wolfSSL/wolfssl/pull/9628/>
* <https://github.com/wolfSSL/wolfssl/pull/9873/>