CVE-2026-21444 | libtpms returns wrong initialization vector when certain symmetric ciphers are used

Exp

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.

Published: 2026-01-02 Last update: 2026-02-25 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-21444 is rated Exploit Available (50/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.01%). 1 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2026-21444

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2026-21444

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-01-03 — 0.01% —

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-21444

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.5 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 1.8 3.6 [email protected]

Weakness enumeration for CVE-2026-21444

OS Trackers for CVE-2026-21444

vendor priority summary link
alpine — CVE-2026-21444: 1 source package rows (libtpms); 4 state rows across 2 repos (3.23-community, edge-community); fixed 0, open 4. https://security.alpinelinux.org/vuln/CVE-2026-21444
debian unimportant CVE-2026-21444 unimportant priority: Debian including 1 source packages (libtpms), 4 status rows across 4 suites (bookworm, forky, sid, trixie): resolved 4. https://security-tracker.debian.org/tracker/CVE-2026-21444
redhat medium — https://access.redhat.com/security/cve/CVE-2026-21444
suse medium — https://www.suse.com/security/cve/CVE-2026-21444/
ubuntu medium CVE-2026-21444 medium priority: Ubuntu including 1 source packages (libtpms), 5 status rows across 5 suites (jammy, noble, plucky, questing, upstream): not-affected 4, released 1. https://ubuntu.com/security/CVE-2026-21444

Affected software / configurations for CVE-2026-21444

Vendor Product Version Raw CPE
libtpms_project libtpms >= 0.10.0, < 0.10.2 cpe:2.3:a:libtpms_project:libtpms:*:*:*:*:*:*:*:*

References for CVE-2026-21444

cvelogic Threat Intelligence