CVE-2026-43075 — ocfs2: fix out-of-bounds write in ocfs2_write_end_inline
In the Linux kernel, the following vulnerability has been resolved: ocfs2: fix out-of-bounds write in ocfs2_write_end_inline KASAN reports a use-after-free write of 4086 bytes in ocfs2_write_end_inline, called from ocfs2_write_end_nolock during a copy_file_range splice fallback on a corrupted ocfs2 filesystem mounted on a loop device. The actual bug is an out-of-bounds write past the inode block buffer, not a true use-after-free. The write overflows into an adjacent freed page, which KASAN reports as UAF. The root cause is that ocfs2_try_to_write_inline_data trusts the on-disk id_count field to determine whether a write fits in inline data. On a corrupted filesystem, id_count can exceed the physical maximum inline data capacity, causing writes to overflow the inode block buffer. Call trace (crash path): vfs_copy_file_range (fs/read_write.c:1634) do_splice_direct splice_direct_to_actor iter_file_splice_write ocfs2_file_write_iter generic_perform_write ocfs2_write_end ocfs2_write_end_nolock (fs/ocfs2/aops.c:1949) ocfs2_write_end_inline (fs/ocfs2/aops.c:1915) memcpy_from_folio <-- KASAN: write OOB So add id_count upper bound check in ocfs2_validate_inode_block() to alongside the existing i_size check to fix it.
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.
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)
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 matching the vulnerability class (memory corruption), errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Linux | Linux |
version 2.6.24≥ 1afc32b952335f665327a1a9001ba1b44bb76fd9 and < 7bc5da4842bed3252d26e742213741a4d0ac1b14≥ 1afc32b952335f665327a1a9001ba1b44bb76fd9 and < 69d3c69ade1e4285ab4ca48fe7acee0767e65604≥ 1afc32b952335f665327a1a9001ba1b44bb76fd9 and < 0c1af902223b6fcedb60904ca0b551254686c7b9≥ 1afc32b952335f665327a1a9001ba1b44bb76fd9 and < 947f953978b0d9463498d548d0f054f5a75be2e9≥ 1afc32b952335f665327a1a9001ba1b44bb76fd9 and < e2c9dc6b6e96f3585f2a1062ca3374a52db0938f≥ 1afc32b952335f665327a1a9001ba1b44bb76fd9 and < 22df7d4de9c5cd42edf855a1de25f2106088c4c6≥ 1afc32b952335f665327a1a9001ba1b44bb76fd9 and < 2e6a254f9cedf51b75cc20b8b92e2209bfa04c3e and 1 more≥ 1afc32b952335f665327a1a9001ba1b44bb76fd9 and < 68f9cc3bbf2ae501770cea7dc0005fc9a85e48ea |
Vulnerable | CVE Program (cve.org) e CISA ADP |
| Linux | Linux Kernel |
version 7.0-rc6version 7.0-rc7≥ 2.6.24.1 and < 6.6.136version 7.0-rc5version 7.0-rc4version 7.0-rc3version 7.0-rc2version 7.0-rc1 and 4 moreversion 2.6.24≥ 6.19 and < 6.19.14≥ 6.13 and < 6.18.24≥ 6.7 and < 6.12.83 |
Vulnerable | NIST National Vulnerability Database |
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 | — | — | 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) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
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.
- Correlate service crashes/restarts with inbound traffic; repeated crashes may indicate attempts.
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · linux/linux
- Record published
- Fix documented
- CVSS changed · 7.8
- Source status changed · → Modified
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 13, 2026 – Oct 13, 2026
References
8 on the record
- git.kernel.org/stable/c/0c1af902223b6fcedb60904ca0b551254686c7b9
- git.kernel.org/stable/c/69d3c69ade1e4285ab4ca48fe7acee0767e65604
- git.kernel.org/stable/c/947f953978b0d9463498d548d0f054f5a75be2e9
- git.kernel.org/stable/c/e2c9dc6b6e96f3585f2a1062ca3374a52db0938f
- git.kernel.org/stable/c/7bc5da4842bed3252d26e742213741a4d0ac1b14
- git.kernel.org/stable/c/22df7d4de9c5cd42edf855a1de25f2106088c4c6
- git.kernel.org/stable/c/68f9cc3bbf2ae501770cea7dc0005fc9a85e48ea
- git.kernel.org/stable/c/2e6a254f9cedf51b75cc20b8b92e2209bfa04c3e
Elsewhere on this site
Related CVEs (same products)
- Critical CVE-2026-99999 ipv4: validate checksum_start before completing checksum 8h
- Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 8h
- 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 CISA SSVC assessment.
- 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-2026-43075 is "ocfs2: fix out-of-bounds write in ocfs2_write_end_inline", 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 0.17% 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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