Medium

CVE-2026-46046 — ext4: fix missing brelse() in ext4_xattr_inode_dec_ref_all()

In the Linux kernel, the following vulnerability has been resolved: ext4: fix missing brelse() in ext4_xattr_inode_dec_ref_all() The commit c8e008b60492 ("ext4: ignore xattrs past end") introduced a refcount leak in when block_csum is false. ext4_xattr_inode_dec_ref_all() calls ext4_get_inode_loc() to get iloc.bh, but never releases it with brelse().

Published May 27, 2026 · Updated Oct 14, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP, GitHub Security Advisories · CNA: Linux

Low

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.

How the score was calculated

EPSS 0.2% (30-day exploitation probability)+1
Technical severity (medium)+3

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation

Not confirmed

Not in CISA KEV — an absence of record, not proof it is unexploited.

EPSS FIRST

0.17%

ahead of 5% of scored CVEs · Oct 14, 2026

Affects

Linux

Linux and 1 more

CVSS base

5.5

Medium · 2 source(s)

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

Documented patch — git.kernel.org (NIST National Vulnerability Database)
Documented patch — git.kernel.org (NIST National Vulnerability Database)
Documented patch — git.kernel.org (NIST National Vulnerability Database)
Documented patch — git.kernel.org (NIST National Vulnerability Database)
Documented patch — git.kernel.org (NIST National Vulnerability Database)
Documented patch — git.kernel.org (NIST National Vulnerability Database)
Documented patch — git.kernel.org (NIST National Vulnerability Database)
Documented patch — git.kernel.org (NIST National Vulnerability Database)

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

Identify exposed assets running the affected vendor/product/version combinations (Linux Linux, Linux Linux Kernel).
Apply the fixed version or the patch documented under Remediation.
Search available logs for exploit probes, errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Vendor	Product	Versions	Status	Source
Linux	Linux	≥ c8e008b60492cf6fd31ef127aea6d02fd3d314cd and < 1e6b0a69bf2c9c819255c7566e4355536d81d9cfversion 6.15≥ 6.14.3 and < 6.15≥ 6.13.12 and < 6.14≥ 5.4.293 and < 5.5≥ 6.12.24 and < 6.12.86≥ 6.6.88 and < 6.6.140≥ 6.1.135 and < 6.1.175 and 12 more ≥ 5.15.181 and < 5.15.209≥ 5.10.237 and < 5.10.258version 836e625b03a666cf93ff5be328c8cb30336db872version 3bc6317033f365ce578eb6039445fb66162722fdversion 6aff941cb0f7d0c897c3698ad2e30672709135e3≥ c8e008b60492cf6fd31ef127aea6d02fd3d314cd and < 77d059519382bd66283e6a4e83ee186e87e7708f≥ c8e008b60492cf6fd31ef127aea6d02fd3d314cd and < f072906688933bf47fabbaf63560be03357c8298≥ eb59cc31b6ea076021d14b04e7faab1636b87d0e and < 097227f1ffe1a85bc3c359f81c71e3d40e06e920≥ 362a90cecd36e8a5c415966d0b75b04a0270e4dd and < 1bc1107a3a403a6d440673ed6666f7b07ef868a8≥ cf9291a3449b04688b81e32621e88de8f4314b54 and < b706d00206a9e82362a9633efbd8b5775650169b≥ f737418b6de31c962c7192777ee4018906975383 and < 153ab2c52355fbebcae622db8e7b506492c73a29≥ 76c365fa7e2a8bb85f0190cdb4b8cdc99b2fdce3 and < dd98a5603a212ea9c96c6982ccdbcc748fdb9a56	Vulnerable	CVE Program (cve.org) e CISA ADP
Linux	Linux Kernel	≥ 5.4.293 and < 5.5≥ 6.19 and < 7.0.4≥ 6.14.3 and < 6.18.27≥ 6.13.12 and < 6.14≥ 6.12.24 and < 6.12.86≥ 6.6.88 and < 6.6.140≥ 6.1.135 and < 6.1.175≥ 5.15.181 and < 5.15.209 and 1 more ≥ 5.10.237 and < 5.10.258	Vulnerable	NIST National Vulnerability Database

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector

Local

Attack complexity

Low

Privileges required

Low

User interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

Score	Version	Severity	Expl.	Impact	Scored by
5.5	CVSS 3.1	Medium	1.8	3.6	nvd@nist.gov via NIST National Vulnerability Database
5.5	CVSS 3.1	Medium	—	—	GitHub, Inc. via GitHub Security Advisories

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H (score shown at the top: nvd@nist.gov)

EPSS over time FIRST

Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.17%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

Local/physical vector: focus on endpoint telemetry (EDR) from affected hosts.

endpoint telemetry (EDR)

Timeline

What happened to this CVE, newest first.

2026
Affected products added · linux/linux
Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
Record published
Oct 13, 2026
Fix documented
Oct 13, 2026 · NIST National Vulnerability Database
CVSS changed · 5.5
Oct 13, 2026 · NIST National Vulnerability Database
Source status changed · → Modified
Oct 13, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 13, 2026 · NIST National Vulnerability Database
CVE published
May 27, 2026 · Linux

Source activity

Repeated readings are counted rather than listed.

2× References added · Oct 14, 2026 – Oct 14, 2026
1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

13 on the record

git.kernel.org/stable/c/f072906688933bf47fabbaf63560be03357c8298
Patch, NIST National Vulnerability Database
git.kernel.org/stable/c/153ab2c52355fbebcae622db8e7b506492c73a29
Patch, NIST National Vulnerability Database
git.kernel.org/stable/c/77d059519382bd66283e6a4e83ee186e87e7708f
Patch, NIST National Vulnerability Database
git.kernel.org/stable/c/097227f1ffe1a85bc3c359f81c71e3d40e06e920
Patch, NIST National Vulnerability Database
git.kernel.org/stable/c/dd98a5603a212ea9c96c6982ccdbcc748fdb9a56
Patch, NIST National Vulnerability Database
git.kernel.org/stable/c/1bc1107a3a403a6d440673ed6666f7b07ef868a8
Patch, NIST National Vulnerability Database
git.kernel.org/stable/c/1e6b0a69bf2c9c819255c7566e4355536d81d9cf
Patch, NIST National Vulnerability Database
git.kernel.org/stable/c/b706d00206a9e82362a9633efbd8b5775650169b
Patch, NIST National Vulnerability Database
github.com/advisories/GHSA-m5xh-rjfq-cc6f
GitHub Security Advisories
nvd.nist.gov/vuln/detail/CVE-2026-46046
GitHub Security Advisories
cert-portal.siemens.com/productcert/html/ssa-457936.html
NIST National Vulnerability Database
cert-portal.siemens.com/productcert/html/ssa-019113.html
NIST National Vulnerability Database
cert-portal.siemens.com/productcert/html/ssa-784472.html
NIST National Vulnerability Database

Elsewhere on this site

Linux
every CVE for this vendor

Related CVEs (same products)

Critical CVE-2026-99999 ipv4: validate checksum_start before completing checksum 9h
Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 9h
Unknown CVE-2026-98427 net/sched: codel: bound the dropping loop per dequeue call 1d
Unknown CVE-2026-98424 wifi: cfg80211: undo netns switch if renaming the wiphy fails 1d
Unknown CVE-2026-98425 wifi: mac80211: don't warn when an IBSS has no channel to scan 1d
Unknown CVE-2026-98426 wifi: mwifiex: fix IRQ leak using wrong index in MSI-X error path 1d

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No CISA SSVC assessment.
No CWE classification.
No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-46046 is "ext4: fix missing brelse() in ext4_xattr_inode_dec_ref_all()", rated Medium. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 5.5 describes technical severity. EPSS 0.17% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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