CVE-2025-49133

Libtpms contains a possible out-of-bound access and abort due to HMAC signing issue

MEDIUM
5.5
CVSS Score
Published: June 10, 2025 at 07:46 PM UTC
Updated: June 17, 2026 at 09:30 AM UTC
2 products affected across 2 vendorsLibtpmsLibtpms

Using libtpms by stefanberger?

Get instant alerts when new vulnerabilities affect libtpms - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Severity
MEDIUM5.5
Exploit prediction
EPSS 0.2%
SSVC
No known exploit

Description

Libtpms is a library that targets the integration of TPM functionality into hypervisors, primarily into Qemu. Libtpms, which is derived from the TPM 2.0 reference implementation code published by the Trusted Computing Group, is prone to a potential out of bounds (OOB) read vulnerability. The vulnerability occurs in the ‘CryptHmacSign’ function with an inconsistent pairing of the signKey and signScheme parameters, where the signKey is ALG_KEYEDHASH key and inScheme is an ECC or RSA scheme. The reported vulnerability is in the ‘CryptHmacSign’ function, which is defined in the "Part 4: Supporting Routines – Code" document, section "7.151 - /tpm/src/crypt/CryptUtil.c ". This vulnerability can be triggered from user-mode applications by sending malicious commands to a TPM 2.0/vTPM (swtpm) whose firmware is based on an affected TCG reference implementation. The effect on libtpms is that it will cause an abort due to the detection of the out-of-bounds access, thus for example making a vTPM (swtpm) unavailable to a VM. This vulnerability is fixed in 0.7.12, 0.8.10, 0.9.7, and 0.10.1.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
LOCAL
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-125

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Free plan, no card