CVE-2026-31433 — ksmbd: fix potencial OOB in get_file_all_info() for compound requests
In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix potencial OOB in get_file_all_info() for compound requests When a compound request consists of QUERY_DIRECTORY + QUERY_INFO (FILE_ALL_INFORMATION) and the first command consumes nearly the entire max_trans_size, get_file_all_info() would blindly call smbConvertToUTF16() with PATH_MAX, causing out-of-bounds write beyond the response buffer. In get_file_all_info(), there was a missing validation check for the client-provided OutputBufferLength before copying the filename into FileName field of the smb2_file_all_info structure. If the filename length exceeds the available buffer space, it could lead to potential buffer overflows or memory corruption during smbConvertToUTF16 conversion. This calculating the actual free buffer size using smb2_calc_max_out_buf_len() and returning -EINVAL if the buffer is insufficient and updating smbConvertToUTF16 to use the actual filename length (clamped by PATH_MAX) to ensure a safe copy operation.
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 0.7% (30-day exploitation probability)+8
- 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)
- 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 6.6≥ 6.1.71 and < 6.1.168≥ 5.15.145 and < 5.15.203≥ e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d and < beef2634f81f1c086208191f7228bce1d366493d≥ e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d and < 9d7032851d6f5adbe2739601ca456c0ad3b422f0≥ e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d and < b0cd9725fe2bcc9f37d096b132318a9060373f5d≥ e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d and < 7aec5a769d2356cbf344d85bcfd36de592ac96a5≥ e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d and < 358cdaa1f7fbf2712cb4c5f6b59cb9a5c673c5fe and 2 more≥ 9f297df20d93411c0b4ddad7f88ba04a7cd36e77 and < 4cca3eff2099b18672934a39cee70aed835d652c≥ f2283680a80571ca82d710bc6ecd8f8beac67d63 and < 3a852f9d1c981fb14f6bf4e24999e0ea8088a7d7 |
Vulnerable | CVE Program (cve.org) e CISA ADP |
| Linux | Linux Kernel |
version 7.0-rc5≥ 5.15.145 and < 5.15.203version 7.0-rc4version 7.0-rc3version 7.0-rc2version 7.0-rc1≥ 6.19 and < 6.19.11≥ 6.13 and < 6.18.21 and 3 more≥ 6.7 and < 6.12.80≥ 6.6 and < 6.6.131≥ 6.1.71 and < 6.1.168 |
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 |
|---|---|---|---|---|---|
| 8.8 | CVSS 3.1 | High | 2.8 | 5.9 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 via NIST National Vulnerability Database |
| 8.8 | CVSS 3.1 | High | — | — | Linux via CVE Program (cve.org) e CISA ADP |
CVSS:3.1/AV:N/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 0.72%
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
- 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 · 8.8
- Source status changed · → Analyzed
- 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
7 on the record
- git.kernel.org/stable/c/358cdaa1f7fbf2712cb4c5f6b59cb9a5c673c5fe
- git.kernel.org/stable/c/9d7032851d6f5adbe2739601ca456c0ad3b422f0
- git.kernel.org/stable/c/7aec5a769d2356cbf344d85bcfd36de592ac96a5
- git.kernel.org/stable/c/3a852f9d1c981fb14f6bf4e24999e0ea8088a7d7
- git.kernel.org/stable/c/b0cd9725fe2bcc9f37d096b132318a9060373f5d
- git.kernel.org/stable/c/4cca3eff2099b18672934a39cee70aed835d652c
- git.kernel.org/stable/c/beef2634f81f1c086208191f7228bce1d366493d
Elsewhere on this site
Related CVEs (same products)
- Critical CVE-2026-99999 ipv4: validate checksum_start before completing checksum 7h
- Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 7h
- 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-2026-31433 is "ksmbd: fix potencial OOB in get_file_all_info() for compound requests", 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 8.8 describes technical severity. EPSS 0.72% 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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