CVE-2025-49133 | Libtpms contains a possible out-of-bound access and abort due to HMAC signing issue

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.

Published: 2025-06-10 Last update: 2025-11-03 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2025-49133 is rated Low Risk (33/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.10%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

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

Exploit prediction scoring system (EPSS) score for CVE-2025-49133

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 2026-04-06 0.01% 0.10% +0.08%
2 2025-06-11 — 0.01% —

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-49133

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.9 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:N/I:N/A:H 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:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.5 4.0 [email protected]
5.5 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H 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:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.8 3.6 [email protected]

Weakness enumeration for CVE-2025-49133

OS Trackers for CVE-2025-49133

vendor priority summary link
alpine medium CVE-2025-49133: 1 source package rows (libtpms); 6 state rows across 3 repos (3.22-community, 3.23-community, edge-community); fixed 3, open 3. https://security.alpinelinux.org/vuln/CVE-2025-49133
debian not yet assigned CVE-2025-49133 not yet assigned 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-2025-49133
redhat medium — https://access.redhat.com/security/cve/CVE-2025-49133
suse medium CVE-2025-49133 severity moderate: SUSE including 131 source package names (hivex-1.3.18-23.module+el8.9.0+18724+20190c23, hivex-devel-1.3.18-23.module+el8.9.0+18724+20190c23, …), 146 product×package rows across 22 product lines (Container suse/sl-micro/6.0/baremetal-os-container, Image SL-Micro, … (22 product lines)): Fixed 146. https://www.suse.com/security/cve/CVE-2025-49133/
ubuntu medium CVE-2025-49133 medium priority: Ubuntu including 1 source packages (libtpms), 5 status rows across 5 suites (jammy, noble, oracular, plucky, upstream): released 5. https://ubuntu.com/security/CVE-2025-49133

Affected software / configurations for CVE-2025-49133

Vendor Product Version Raw CPE
libtpms_project libtpms 0.7.11 cpe:2.3:a:libtpms_project:libtpms:0.7.11:*:*:*:*:*:*:*
libtpms_project libtpms 0.8.9 cpe:2.3:a:libtpms_project:libtpms:0.8.9:*:*:*:*:*:*:*
libtpms_project libtpms 0.9.6 cpe:2.3:a:libtpms_project:libtpms:0.9.6:*:*:*:*:*:*:*
libtpms_project libtpms 0.10.0 cpe:2.3:a:libtpms_project:libtpms:0.10.0:*:*:*:*:*:*:*

References for CVE-2025-49133

cvelogic Threat Intelligence