VulnerabilityPublished 28 May 2026Updated 19 Oct 2026

CVE-2026-46124: Linux kernel · Out-of-bounds Read

Affects Linux kernelSource CVE Database V5

Mentioned vulnerabilities

CVE-2025-37780

Not known to be exploited · CVSS 7.5 High · fixed in ee0024f5a7e3c73aa253869fae9650ae054093ca : patch Linux kernel soon.

Data as of 26 Oct 2026, 23:35 UTC

CVSS 3.1 base score

7.5High

How severe the flaw is on the 0–10 CVSS scale.

EPSS

0.4% chance of exploitation in 30 days – higher than 40% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

Exploitation: No evidence of active exploitation and no public proof of concept
Automatable: Attackers can reliably automate steps 1–4 of the kill chain
Technical impact: Limited control over the software or limited information exposure

CISA SSVC assessment, 2026-10-16.

Patch

Available – fixed in ee0024f5a7e3c73aa253869fae9650ae054093ca, bb0988ed4f2e26d59bbb58f644cb3a55b7521e21, afbafeddf23db13fe2edb2d5c0bf4bbb13d7881b +12

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: High
Integrity: None
Availability: None

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: High: There is total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 28 May 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.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade to a fixed release listed under Affected software.

Affected software

Product	Affected	Fixed in
LinuxLinux	Affected >=5.10.237 <5.10.258 >=5.15.181 <5.15.209 >=6.1.135 <6.1.175 >=6.6.88 <6.6.140 >=6.12.25 <6.12.88 >=5.4.293 <5.5 >=6.14.4 <6.15	Fixed in ee0024f5a7e3c73aa253869fae9650ae054093ca bb0988ed4f2e26d59bbb58f644cb3a55b7521e21 afbafeddf23db13fe2edb2d5c0bf4bbb13d7881b 24376458138387fb251e782e624c7776e9826796 908a76f0b1038035e6ebb4f2293ce079f92e0a02 31dbb4ba0f719ae7774e4c0c95172c9bf81692f5 6.15 6.12.88 6.6.140 6.1.175 5.15.209 5.10.258 5.5 4c721a1d9b3c4fcaf59cc9b2281e3ec5a043e1a6 0a1af74ae2177bda3aee0837a0546309aa539d0d
LinuxLinux	Affected =6.15	Fixed in–

AI-suggested

This vulnerability has been fixed in Linux kernel versions 5.10.258, 5.15.209, 6.1.175, 6.6.140, 6.12.88, 6.15, and later. Users should upgrade to these or newer kernel versions to remediate the issue. No additional mitigation is required beyond applying the official fix.

Description

CVE-2026-46124 is a vulnerability in the Linux kernel's isofs filesystem NFS export code. It involves insufficient validation of block numbers derived from NFS file handles, allowing an attacker with authenticated NFS access to cause the server to read arbitrary in-range blocks from the backing device. This can lead to disclosure of unintended data as directory metadata. The issue affects specific Linux kernel versions and has been fixed in later releases.

Impact

An authenticated NFS client can cause the server to read arbitrary in-range blocks from the backing device, potentially exposing unintended data as directory metadata to the client. There is no memory safety violation or code execution impact. The impact is limited to information disclosure of adjacent-partition data on the same block device.

Summary

The vulnerability arises because isofs_fh_to_dentry() and isofs_fh_to_parent() pass attacker-controlled block numbers from NFS file handles to isofs_export_iget(), which only rejects block number zero before calling isofs_iget() and sb_bread(). Although sb_bread() returns NULL for out-of-range blocks, in-range blocks can cause the server to read unintended data from the backing device, which is then exposed to the NFS client as directory metadata. This flaw is a follow-up to CVE-2025-37780 and is mitigated by adding a check in isofs_export_iget() to reject block numbers greater than or equal to the number of zones in the isofs superblock. The vulnerability requires an authenticated NFS peer and a narrow deployment surface (isofs exported over NFS from loop-mounted images).

CWE-125Out-of-bounds Read (opens in a new tab)
Base weaknessCWE Top 25 (2025): #8
The product reads data past the end, or before the beginning, of the intended buffer.
Implementation · Input Validation
Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
Architecture and Design · Language Selection
Use a language that provides appropriate memory abstractions.
OWASP Cheat Sheets
XML Security (opens in a new tab)
Mass Assignment (opens in a new tab)
OWASP ASVS 4.0.3
V13.3.1 (opens in a new tab)
V5.1.4 (opens in a new tab)
V5.1.3 (opens in a new tab)
Attack patterns
Overread Buffers (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 26 Oct 2026, 23:35 UTC

WeaknessesCWE-125

Technical details

References

Community reviews

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