CVE-2025-71077

Local service interruption via unbounded PCR-bank count

Published Jan 13, 2026 · Updated Jan 13, 2026

Improper input validation in the Linux Kernel allows local users to interrupt service through a malformed TPM2 PCR-allocation response. tpm2_get_pcr_allocation() trusts the PCR-bank count returned by external TPM I/O without enforcing the eight-bank limit before processing the allocation. Low-privilege local access is required, and exploitation can make the kernel unavailable without reported confidentiality or integrity impact.

CVSS severity5.5
Medium
EPSS probability0.14%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in the Linux Kernel allows local users to interrupt service through a malformed TPM2 PCR-allocation response. tpm2_get_pcr_allocation() trusts the PCR-bank count returned by external TPM I/O without enforcing the eight-bank limit before processing the allocation. Low-privilege local access is required, and exploitation can make the kernel unavailable without reported confidentiality or integrity impact.

The record

CVE
CVE-2025-71077
Published
Jan 13, 2026
Updated
Jan 13, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
T1499
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Jan 13, 2026CVE publishedPublication date reported by the CVE source.
  2. Jan 13, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=5.1
  2. Affected versionversion=bcfff8384f6c4e6627676ef07ccad9cfacd67849 <858344bc9210bea9ab2bdc7e9e331ba84c164e50
  3. Affected versionversion=bcfff8384f6c4e6627676ef07ccad9cfacd67849 <b69492161c056d36789aee42a87a33c18c8ed5e1
  4. Affected versionversion=bcfff8384f6c4e6627676ef07ccad9cfacd67849 <ceb70d31da5671d298bad94ae6c20e4bbb800f96
  5. Affected versionversion=bcfff8384f6c4e6627676ef07ccad9cfacd67849 <d88481653d74d622d1d0d2c9bad845fc2cc6fd23
  6. Affected versionversion=bcfff8384f6c4e6627676ef07ccad9cfacd67849 <faf07e611dfa464b201223a7253e9dc5ee0f3c9e

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=5.1; version=bcfff8384f6c4e6627676ef07ccad9cfacd67849 <858344bc9210bea9ab2bdc7e9e331ba84c164e50; version=bcfff8384f6c4e6627676ef07ccad9cfacd67849 <b69492161c056d36789aee42a87a33c18c8ed5e1; version=bcfff8384f6c4e6627676ef07ccad9cfacd67849 <ceb70d31da5671d298bad94ae6c20e4bbb800f96; version=bcfff8384f6c4e6627676ef07ccad9cfacd67849 <d88481653d74d622d1d0d2c9bad845fc2cc6fd23; version=bcfff8384f6c4e6627676ef07ccad9cfacd67849 <faf07e611dfa464b201223a7253e9dc5ee0f3c9e

Published CVSS scores

5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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