Linux Kernel: security vulnerability (CVE-2026-80881)
Published Last modified Sources: Ubuntu, HKCERT, SUSE, BSI, CVE.org, EUVD
What is affected, what to do
In the Linux kernel, the following vulnerability has been resolved: ocfs2: fix buffer head management in ocfs2_read_blocks() In ocfs2_read_blocks(), caller should't assume that buffer head returned by 'sb_getblk()' is exclusively owned and so 'put_bh()' always drops b_count from 1 to 0. If it is not so, buffer head remains on hold and likely to be returned by the next call to 'sb_getblk()' unchanged - that is, with BH_Uptodate bit set even if it has failed validation previously, thus allowing to insert that buffer head into OCFS2 metadata cache and submit it to upper layers. To avoid such a scenario, BH_Uptodate should be cleared immediately after 'validate()' callback has detected some data inconsistency.
The available sources name no fixed version. Check the vendor guidance in the references below.
Conflicting version data — version display is hidden until the data is resolved.
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Metrics
—
XIEM Effective CVSS
No value is available for this vulnerability.
0.0
CVSS v3
Severity Not rated on the scale from 0 to 10.
Source: Ubuntu, HKCERT, SUSE, BSI, CVE.org, EUVD
0.2 %
EPSS score
Low — model estimates < 1% exploitation likelihood.
Source: FIRST EPSS, percentile 5.8
Show all metrics
- Severity
- Not rated
Priority (0–325)
The priority score is a consolidated metric that condenses several individual signals into a single, action-guiding ranking: technical severity (CVSS), exploitation likelihood (EPSS), known-exploited status (KEV) and the context of the affected asset. The aim is to answer the only truly important question in vulnerability management: what first?
Read in glossary- 24.34 Methodology
Exploit maturity
An exploit is code or a technique that specifically uses a concrete vulnerability to force unintended behaviour — such as executing code or escalating privileges. It is the tool that turns a theoretical flaw into a practical attack.
Read in glossary- no public PoC known
CVSS v3
CVSS is the globally established, open standard for assessing the technical severity of a vulnerability on a scale from 0 to 10. It describes how easily a flaw can be exploited and what damage it can cause — but not how likely its actual exploitation is. CVSS and the complementary EPSS deliberately answer different questions.
Read in glossary- 0.0
EPSS score
The EPSS score is the absolute model output for an individual vulnerability: the estimated probability of real-world exploitation within the next 30 days, expressed as a value between 0 and 1 (i.e. 0 % to 100 %). A score of 0.42 means „the model estimates a 42 % chance of real-world exploitation within 30 days“.
Read in glossary- 0.2 %
- Low — model estimates < 1% exploitation likelihood.
EPSS percentile
The EPSS percentile is the relative position of a vulnerability within all EPSS-scored CVEs, expressed as a value between 0 and 1. A percentile of 0.90 means „this CVE has a higher EPSS score than 90 % of all other scored CVEs“. Unlike the EPSS score, it is not a probability — but a positioning within a ranking.
Read in glossary- 5.8
- Low — this CVE sits in the lower 10% of all CVEs scored today.
KEV status
The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching.
Read in glossary- —
- Published
Detection rules
No NEOSEC detection rule is available for this vulnerability yet.
Classification under NIS2 and CRA
Rule-based classification from exploitation status and severity. It does not replace a case-by-case assessment.
NIS2
NIS2 is EU Directive (EU) 2022/2555 to raise the level of cybersecurity across the Union. It substantially broadens obligations compared with the first NIS directive: more sectors, mandatory risk management, staged reporting duties and personal accountability of senior management.
Read in glossary- Handle the vulnerability in regular vulnerability handling under Art. 21(2)(e) NIS2.
CRA
The CRA is EU Regulation (EU) 2024/2847 setting horizontal cybersecurity requirements for „products with digital elements“ — from industrial controllers and software to connected consumer devices. For the first time manufacturers must ensure security across the entire product lifecycle, handle vulnerabilities and provide security updates.
Read in glossary- From 11.12.2027, Annex I Part II CRA requires manufacturers of affected products with digital elements to handle vulnerabilities without delay and provide security updates.
ISO/IEC 27001
ISO/IEC 27001 is the internationally leading standard for an information security management system (ISMS). It describes a risk-based, process-oriented framework to systematically plan, implement, review and improve information security.
Read in glossary- Control A.8.8, management of technical vulnerabilities: assess relevance to your systems, plan remediation and keep evidence.
Description
In the Linux kernel, the following vulnerability has been resolved: ocfs2: fix buffer head management in ocfs2_read_blocks() In ocfs2_read_blocks(), caller should't assume that buffer head returned by 'sb_getblk()' is exclusively owned and so 'put_bh()' always drops b_count from 1 to 0. If it is not so, buffer head remains on hold and likely to be returned by the next call to 'sb_getblk()' unchanged - that is, with BH_Uptodate bit set even if it has failed validation previously, thus allowing to insert that buffer head into OCFS2 metadata cache and submit it to upper layers. To avoid such a scenario, BH_Uptodate should be cleared immediately after 'validate()' callback has detected some data inconsistency.
Source: Ubuntu Security Notices, HKCERT (CC BY 3.0 HK) · HKCERT rating: medium, suse_csaf, BSI WID Portal, BSI CSAF, CVE.org (MITRE), ENISA EUVD, cvelistv5
Affected products
The following versions are affected. Older releases of the same product line are also vulnerable unless stated otherwise.
| Affected versions | Fixed in | ||
|---|---|---|---|
| Linux | Linux |
|
|
| Red Hat | OpenShift |
|
|
Vendors and products
Affected operating systems
| Linux | ubuntu | linux | noble |
| Linux | ubuntu | linux | resolute |
| Linux | ubuntu | linux-aws | noble |
| Linux | ubuntu | linux-aws | resolute |
| Linux | ubuntu | linux-aws-6.8 | jammy |
| Linux | ubuntu | linux-aws-7.0 | noble |
| Linux | ubuntu | linux-aws-fips | noble |
| Linux | ubuntu | linux-azure | noble |
| Linux | ubuntu | linux-azure | resolute |
| Linux | ubuntu | linux-azure-6.8 | jammy |
| Linux | ubuntu | linux-azure-7.0 | noble |
| Linux | ubuntu | linux-azure-fde | noble |
| Linux | ubuntu | linux-azure-fde | resolute |
| Linux | ubuntu | linux-azure-fde-6.8 | jammy |
| Linux | ubuntu | linux-azure-fde-7.0 | noble |
| Linux | ubuntu | linux-azure-fips | noble |
| Linux | ubuntu | linux-fips | noble |
| Linux | ubuntu | linux-gcp | noble |
| Linux | ubuntu | linux-gcp | resolute |
| Linux | ubuntu | linux-gcp-6.8 | jammy |
| Linux | ubuntu | linux-gcp-7.0 | noble |
| Linux | ubuntu | linux-gcp-fips | noble |
| Linux | ubuntu | linux-gke | noble |
| Linux | ubuntu | linux-gke | resolute |
References & sources
- git.kernel.orgstable/c/a4eae1499c760949a93459d11390bd1fd823d31deuvd
- git.kernel.orgstable/c/4ab17e328522a4df5fe0f0dcf39098118b1feeaaeuvd
- git.kernel.orgstable/c/5927acb3e2c99985a14adecd9d1b67ba191c622deuvd
- git.kernel.orgstable/c/ecb3f9386f4353034caef77239473c627232db17euvd
- git.kernel.orgstable/c/61f7a5acb3bf8fc97dad78f54b1e8d0e1c819766euvd
- git.kernel.orgstable/c/0e389fc290c350c67591abf4c367119f4689f310euvd
- git.kernel.orgstable/c/9e7a057934cdd58e4cc94350bcfe5367bbee0f8eeuvd
- git.kernel.orgstable/c/6371a07148ee979af22a9d6f4c277462953a9a4aeuvd
Changes to this CVE
Who changed this CVE and when: NVD (analysis, affected products, CVSS), the CVE publisher (CNA) and additional providers such as CISA (ADP).
ReceivedLinux
Description added or changed
New references:- https://git.kernel.org/stable/c/0e389fc290c350c67591abf4c367119f4689f310
- https://git.kernel.org/stable/c/4ab17e328522a4df5fe0f0dcf39098118b1feeaa
- https://git.kernel.org/stable/c/5927acb3e2c99985a14adecd9d1b67ba191c622d
- https://git.kernel.org/stable/c/61f7a5acb3bf8fc97dad78f54b1e8d0e1c819766
and 4 more references
Show 10 original changes
Individual changes of this event as published by NVD Type Action Before After Description added —In the Linux kernel, the following vulnerability has been resolved: ocfs2: fix buffer head management in ocfs2_read_blocks() In ocfs2_read_blocks(), caller should't assume that buffer head returned by 'sb_getblk()' is exclusively owned and so 'put_bh()' always drops b_count from 1 to 0. If it is not so, buffer head remains on hold and likely to be returned by the next call to 'sb_getblk()' unchanged - that is, with BH_Uptodate bit set even if it has failed validation previously, thus allowing to insert that buffer head into OCFS2 metadata cache and submit it to upper layers. To avoid such a scenario, BH_Uptodate should be cleared immediately after 'validate()' callback has detected some data inconsistency.Affected versions (publisher) added —New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/80xxx/CVE-2026-80881.json">CVE-2026-80881</a>Reference added —https://git.kernel.org/stable/c/0e389fc290c350c67591abf4c367119f4689f310Reference added —https://git.kernel.org/stable/c/4ab17e328522a4df5fe0f0dcf39098118b1feeaaReference added —https://git.kernel.org/stable/c/5927acb3e2c99985a14adecd9d1b67ba191c622dReference added —https://git.kernel.org/stable/c/61f7a5acb3bf8fc97dad78f54b1e8d0e1c819766Reference added —https://git.kernel.org/stable/c/6371a07148ee979af22a9d6f4c277462953a9a4aReference added —https://git.kernel.org/stable/c/9e7a057934cdd58e4cc94350bcfe5367bbee0f8eReference added —https://git.kernel.org/stable/c/a4eae1499c760949a93459d11390bd1fd823d31dReference added —https://git.kernel.org/stable/c/ecb3f9386f4353034caef77239473c627232db17Source identifier: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
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<a href="https://intel.neosec.eu/en/cve/CVE-2026-80881"><img src="https://intel.neosec.eu/badge/cve/CVE-2026-80881.svg?lang=en" alt="CVE-2026-80881 – NEOSEC Intel" height="20"></a>