Linux Kernel: security vulnerability (CVE-2026-97503)
Published Last modified Sources: CVE.org, Msrc Update Guide, BSI
What is affected, what to do
In the Linux kernel, the following vulnerability has been resolved: genirq/proc: Size interrupt directory names for 10-digit interrupt numbers /proc/irq/<n>/ directory names are built in `char name[10]` buffers with `sprintf(name, "%u", irq)`. Ten-digit IRQ numbers already need 11 bytes including the trailing NUL, and current sparse-IRQ configurations allow interrupt numbers in that range.
Update Linux Kernel to version 6.6.160, Linux Kernel to version 6.12.114, Linux Kernel to version 6.18.53.
- Affected
- Linux Kernel
lt 6.5..6.6.160 - Linux Kernel
lt 6.7..6.12.114 - Linux Kernel
lt 6.13..6.18.53 - Linux Kernel
lt 6.19..7.2
- Linux Kernel
- Fixed in
- Linux Kernel
6.6.160 - Linux Kernel
6.12.114 - Linux Kernel
6.18.53 - Linux Kernel
7.2
- Linux Kernel
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Metrics
6.4
Priority
XIEM Effective CVSS: highest available CVSS rating from NVD and vendor data.
Source: Vendor (CNA), CVSS v3
6.4
CVSS v3
Severity Medium on the scale from 0 to 10.
Source: CVE.org, Msrc Update Guide, BSI
0.2 %
EPSS score
Low — model estimates < 1% exploitation likelihood.
Source: FIRST EPSS, percentile 4.8
Show all metrics
- Severity
- Medium
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- 61.48 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
XIEM Effective CVSS
XIEM® is the tiered managed-security operating model from NEOSEC and a registered trademark of NEOSEC GmbH. It extends classic SIEM — the central collection, normalisation and correlation of security-relevant events — with endpoint forensics, network visibility and deception technology, and consolidates them into three building tiers: Sentry, Orchestrate and Command.
Read in glossary- 6.4 Methodology
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- 6.4
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- 4.8
- 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: genirq/proc: Size interrupt directory names for 10-digit interrupt numbers /proc/irq/<n>/ directory names are built in `char name[10]` buffers with `sprintf(name, "%u", irq)`. Ten-digit IRQ numbers already need 11 bytes including the trailing NUL, and current sparse-IRQ configurations allow interrupt numbers in that range. Size the temporary name buffer for the current decimal form and switch to bounded formatting when creating or removing the proc entry.
Source: NVD (NIST), cvelistv5, Microsoft Security Update Guide, BSI WID Portal, BSI CSAF
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 |
|
|
Vendors and products
References & sources
- git.kernel.orgstable/c/d4b22fbae70037299e96539c330e4a1054b28a91
- git.kernel.orgstable/c/c2c7983c93f5d86962318be7e7298f1bc3feb1a6
- git.kernel.orgstable/c/a8adf64fe7fd5d7c476769a043ee56eda7b775ce
- git.kernel.orgstable/c/488bcd7fd3e9a2ad647b71b505a269fdb28753c4
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).
Record modifiedLinux
Show 3 original changes
Individual changes of this event as published by NVD Type Action Before After Affected versions (publisher) added —Affected value modified. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/97xxx/CVE-2026-97503.json">CVE-2026-97503</a>Reference added —https://git.kernel.org/stable/c/488bcd7fd3e9a2ad647b71b505a269fdb28753c4Reference added —https://git.kernel.org/stable/c/a8adf64fe7fd5d7c476769a043ee56eda7b775ceSource identifier: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Record modifiedLinux
1 individual change: Affected versions (publisher)
Show the original change
Individual changes of this event as published by NVD Type Action Before After Affected versions (publisher) added —Affected value modified. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/97xxx/CVE-2026-97503.json">CVE-2026-97503</a>Source identifier: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
ReceivedLinux
Description added or changed
Show 4 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: genirq/proc: Size interrupt directory names for 10-digit interrupt numbers /proc/irq/<n>/ directory names are built in `char name[10]` buffers with `sprintf(name, "%u", irq)`. Ten-digit IRQ numbers already need 11 bytes including the trailing NUL, and current sparse-IRQ configurations allow interrupt numbers in that range. Size the temporary name buffer for the current decimal form and switch to bounded formatting when creating or removing the proc entry.Affected versions (publisher) added —New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/97xxx/CVE-2026-97503.json">CVE-2026-97503</a>Reference added —https://git.kernel.org/stable/c/c2c7983c93f5d86962318be7e7298f1bc3feb1a6Reference added —https://git.kernel.org/stable/c/d4b22fbae70037299e96539c330e4a1054b28a91Source identifier: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
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<a href="https://intel.neosec.eu/en/cve/CVE-2026-97503"><img src="https://intel.neosec.eu/badge/cve/CVE-2026-97503.svg?lang=en" alt="CVE-2026-97503 – NEOSEC Intel" height="20"></a>