CVE-2025-71077: Linux kernel · tpm: Cap the number of PCR banks
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 5.5 Medium · fixed in 5.15.0-1103.110~20.04.1 : update Linux kernel when convenient.
Data as of 26 Oct 2026, 14:05 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 3% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 5.15.0-1103.110~20.04.1, 5.15.0-1110.119~20.04.1, 5.15.0-1103.112~20.04.1 +70
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 13 Jan 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 25.10linuxpkg:deb/ubuntu/linux@6.17.0-22.22?arch=source&distro=questingOther threats | Affected
| Fixed in
|
Ubuntu 25.10linux-awspkg:deb/ubuntu/linux-aws@6.17.0-1012.12?arch=source&distro=questingOther threats | Affected
| Fixed in
|
Ubuntu 25.10linux-azurepkg:deb/ubuntu/linux-azure@6.17.0-1013.13?arch=source&distro=questingOther threats | Affected
| Fixed in
|
Ubuntu 25.10linux-azure-fdepkg:deb/ubuntu/linux-azure-fde@6.17.0-1017.17?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10linux-gcppkg:deb/ubuntu/linux-gcp@6.17.0-1012.12?arch=source&distro=questingOther threats | Affected
| Fixed in
|
Ubuntu 25.10linux-oraclepkg:deb/ubuntu/linux-oracle@6.17.0-1011.11?arch=source&distro=questingOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
An official patch is available and should be applied to affected Linux kernel versions. The vendor manages remediation through updated kernel packages for affected Ubuntu releases. Users should update their Linux kernel to the fixed versions as per the Ubuntu Security Notice USN-8096-1. No additional mitigation actions are required beyond applying the official fix.
Description
A vulnerability in the Linux kernel's TPM driver was resolved by capping the number of PCR banks to eight. The function tpm2_get_pcr_allocation() previously did not limit the number of banks, which could allow out-of-bounds values from external I/O to cause harm. This issue affects multiple Linux kernel versions prior to specific patched releases. The vulnerability has a medium severity with a CVSS score of 5.5 and does not impact confidentiality or integrity but can affect availability. Official patches are available from the vendor to address this issue.
References
- ubuntu.com/security/CVE-2025-71077 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2025-71077 (opens in a new tab)
- git.kernel.org/linus/faf07e611dfa464b201223a7253e9dc5ee0f3c9e (opens in a new tab)
- git.kernel.org/stable/c/858344bc9210bea9ab2bdc7e9e331ba84c164e50 (opens in a new tab)
- git.kernel.org/stable/c/b69492161c056d36789aee42a87a33c18c8ed5e1 (opens in a new tab)
- git.kernel.org/stable/c/ceb70d31da5671d298bad94ae6c20e4bbb800f96 (opens in a new tab)
- git.kernel.org/stable/c/d88481653d74d622d1d0d2c9bad845fc2cc6fd23 (opens in a new tab)
- git.kernel.org/stable/c/faf07e611dfa464b201223a7253e9dc5ee0f3c9e (opens in a new tab)
- ubuntu.com/security/notices/USN-8096-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8096-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8096-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8096-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-8116-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8096-5 (opens in a new tab)
- ubuntu.com/security/notices/USN-8141-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8163-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8163-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8177-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8179-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8177-2 (opens in a new tab)