---
title: CVE-2026-21444
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-2026-21444
---

# CVE-2026-21444

Publication date 2 January 2026

Last updated 7 January 2026

---

Ubuntu priority

**Medium**

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

## Cvss 3 Severity Score

**5.5 · Medium**

[Score breakdown](https://ubuntu.com/security/CVE-2026-21444#impact-score)

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## Description

libtpms, a library that provides software emulation of a Trusted Platform
Module, has a flaw in versions 0.10.0 and 0.10.1. The commonly used
integration of libtpms with OpenSSL 3.x contained a vulnerability related
to the returned IV (initialization vector) when certain symmetric ciphers
were used. Instead of returning the last IV it returned the initial IV to
the caller, thus weakening the subsequent encryption and decryption steps.
The highest threat from this vulnerability is to data confidentiality.
Version 0.10.2 fixes the issue. No known workarounds are available.

[Read the notes from the security team](https://ubuntu.com/security/CVE-2026-21444#notes)

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| libtpms | 25.10 questing | Not affected |
| 25.04 plucky | Not affected |
| 24.04 LTS noble | Not affected |
| 22.04 LTS jammy | Not affected |

---

* [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)
* [What do statuses mean?](https://ubuntu.com/security/cves/about#statuses)
* [Patch details](https://ubuntu.com/security/CVE-2026-21444#patch-details)

## Notes

---

### [mdeslaur](https://launchpad.net/~mdeslaur)

per Debian, introduced in v0.10.0-rc1 via
https://github.com/stefanberger/libtpms/commit/d08b929dede77bee05bd674d48c7a0548528ca9c

### Patch details

For informational purposes only. We recommend not to cherry-pick updates. [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)

| Package | Patch details |
| --- | --- |
| libtpms | * Upstream:   [33c9ff0](https://github.com/stefanberger/libtpms/commit/33c9ff074cb16c1841ce7d7f33643c17c426743a) |

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

5.5 · Medium

* Base metrics

  | Parameter | Value |
  | --- | --- |
  | Attack vector | Local |
  | Attack complexity | Low |
  | Privileges required | Low |
  | User interaction | None |
  | Scope | Unchanged |
  | Confidentiality impact | High |
  | Integrity impact | None |
  | Availability impact | None |
* Scores

  | Parameter | Value |
  | --- | --- |
  | Base score | 5.5 · Medium |
  | Exploitability score | - |
  | Impact score | - |

**Vector:** CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-21444)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2026-21444)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2026-21444)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2026-21444)

### Other references

* <https://www.cve.org/CVERecord?id=CVE-2026-21444>
* <https://github.com/stefanberger/libtpms/security/advisories/GHSA-7jxr-4j3g-p34f>