Vulnerability · Published Jan 2, 2026 · Assigned by GitHub_M
CVE-2026-21444libtpms returns wrong initialization vector when certain symmetric ciphers are used
Medium 5.5
In plain English
A medium-severity broken cryptography in libtpms from stefanberger. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.1% (higher than 0% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:14 | libtpms | 0.10.2-1 | DEBIAN-CVE-2026-21444 |
| Ubuntu:22.04:LTS | libtpms | no fix listed | UBUNTU-CVE-2026-21444 |
| Ubuntu:24.04:LTS | libtpms | no fix listed | UBUNTU-CVE-2026-21444 |
| Ubuntu:25.10 | libtpms | no fix listed | UBUNTU-CVE-2026-21444 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| stefanberger | libtpms | >= 0.10.0, < 0.10.2 |
Weakness: CWE-327, CWE-330 · Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
References
- https://github.com/stefanberger/libtpms/security/advisories/GHSA-7jxr-4j3g-p34f x_refsource_CONFIRM
- https://github.com/stefanberger/libtpms/issues/541 x_refsource_MISC
- https://github.com/stefanberger/libtpms/commit/33c9ff074cb16c1841ce7d7f33643c17c426743a x_refsource_MISC