CVE-2023-54062 — ext4: fix invalid free tracking in ext4_xattr_move_to_block()
In the Linux kernel, the following vulnerability has been resolved: ext4: fix invalid free tracking in ext4_xattr_move_to_block() In ext4_xattr_move_to_block(), the value of the extended attribute which we need to move to an external block may be allocated by kvmalloc() if the value is stored in an external inode. So at the end of the function the code tried to check if this was the case by testing entry->e_value_inum. However, at this point, the pointer to the xattr entry is no longer valid, because it was removed from the original location where it had been stored. So we could end up calling kvfree() on a pointer which was not allocated by kvmalloc(); or we could also potentially leak memory by not freeing the buffer when it should be freed. Fix this by storing whether it should be freed in a separate variable.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.2% (30-day exploitation probability)+1
- Technical severity (high)+6
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.
CISA SSVC assessment CISA
Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.
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).
- No fix documented in the sources: reduce exposure and monitor the vendor advisory.
- 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 |
≥ 1e9d62d252812575ded7c620d8fc67c32ff06c16 and < b87c7cdf2bed4928b899e1ce91ef0d147017ba45version 6.3≥ 6.2.3 and < 6.2.16≥ 6.1.16 and < 6.1.29≥ 5.15.99 and < 5.15.112≥ 5.10.173 and < 5.10.180≥ 5.4.235 and < 5.4.243≥ 4.19.276 and < 4.19.283 and 9 more≥ 4.14.308 and < 4.14.315≥ c7851208abffe5ae4deb01cf48763911dc14fc67 and < 76887be2a96193cd11be818551b8934ecdb3123f≥ 1e9d62d252812575ded7c620d8fc67c32ff06c16 and < b2fab1807d26acd1c6115b95b5eddd697d84751b≥ d2efaf8c870c7067b8d1779773134f3481cd8f68 and < a18670395e5f28acddeca037c5e4bd2ea961b70a≥ 8b6d06b3be7648b3b0f428558293ddf6e2cb94bf and < c5fa4eedddd1c8342ce533cb401c0e693e55b4e3≥ a6744e14ce7045ab1a728bde9595f62fbd39f1d2 and < 8beaa3cb293a8f7bacf711cf52201d59859dbc40≥ d738789ae9ec47d3458a008788f3cdc862ebf0cb and < 1a8822343e67432b658145d2760a524c884da9d4≥ 3b28c799a1334adb5a19f42f03abe0d8cbb05938 and < ba04d6af5ac440a6d5a2d35dc1d8e2cb0323550a≥ f5cdc6a7339f250d44d4d469ed7a474ac0d6c7a7 and < f30f3391d089dc91aef91d08f4b04a6c0df2b067 |
Vulnerable | CVE Program (cve.org) e CISA ADP |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
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 |
|---|---|---|---|---|---|
| 7.8 | CVSS 3.1 | High | 1.8 | 5.9 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 via NIST National Vulnerability Database |
| 7.8 | CVSS 3.1 | High | — | — | GitHub, Inc. via GitHub Security Advisories |
| 7.8 | CVSS 3.1 | High | — | — | Linux via CVE Program (cve.org) e CISA ADP |
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H (score shown at the top: 416baaa9-dc9f-4396-8d5f-8c081fb06d67) EPSS over time FIRST
Oct 13, 2026 → Oct 15, 2026 · 3 reading(s) · max 0.16%
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.
Timeline
What happened to this CVE, newest first.
- 2026
- SSVC assessment updated
- Affected products added · linux/linux
- Record published
- CVSS changed · 7.8
- Source status changed · → Deferred
- Record created in this database
- 2025
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× References added · Oct 15, 2026 – Oct 15, 2026
- 1× Official description updated · Oct 13, 2026 – Oct 13, 2026
References
11 on the record
- git.kernel.org/stable/c/b2fab1807d26acd1c6115b95b5eddd697d84751b
- git.kernel.org/stable/c/b87c7cdf2bed4928b899e1ce91ef0d147017ba45
- nvd.nist.gov/vuln/detail/CVE-2023-54062
- git.kernel.org/stable/c/76887be2a96193cd11be818551b8934ecdb3123f
- git.kernel.org/stable/c/a18670395e5f28acddeca037c5e4bd2ea961b70a
- git.kernel.org/stable/c/8beaa3cb293a8f7bacf711cf52201d59859dbc40
- git.kernel.org/stable/c/ba04d6af5ac440a6d5a2d35dc1d8e2cb0323550a
- git.kernel.org/stable/c/1a8822343e67432b658145d2760a524c884da9d4
- github.com/advisories/GHSA-3m76-cj86-mwp4
- git.kernel.org/stable/c/f30f3391d089dc91aef91d08f4b04a6c0df2b067
- git.kernel.org/stable/c/c5fa4eedddd1c8342ce533cb401c0e693e55b4e3
Elsewhere on this site
Related CVEs (same products)
- Critical CVE-2026-99999 ipv4: validate checksum_start before completing checksum 22h
- Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 22h
- 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
- Unknown CVE-2026-98427 net/sched: codel: bound the dropping loop per dequeue call 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 fixed version, patch or mitigation documented.
- 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-2023-54062 is "ext4: fix invalid free tracking in ext4_xattr_move_to_block()", rated High. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 7.8 describes technical severity. EPSS 0.16% 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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