CVE-2026-53010 — Linux kernel ksmbd use-after-free in smb2_open durable reconnect
In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix use-after-free in smb2_open during durable reconnect In smb2_open, the call to ksmbd_put_durable_fd(fp) drops the reference to the durable file descriptor early during the durable reconnect process. If an error occurs subsequently (eg, ksmbd_iov_pin_rsp fails) or a scavenger accesses the file, it leads to a use-after-free when accessing fp properties (eg fp->create_time). Move the single put to the end of the function below err_out2 so fp stays valid until smb2_open returns.
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 0.4% (30-day exploitation probability)+6
- Technical severity (critical)+10
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)
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).
- The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
- 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 | ≥ 8df4bcdb0a4232192b2445256c39b787d58ef14d and < f0ff7f12398e85b3a11745ff7feab6246f3d75c2≥ c8efcc786146a951091588e5fa7e3c754850cb3c and < 4db3dcac84c2f14a45ae201efb38de1fb1bfc009≥ c8efcc786146a951091588e5fa7e3c754850cb3c and < ce2e164c1c51c3f7813b80f8c926836e896bcbb3≥ c8efcc786146a951091588e5fa7e3c754850cb3c and < 97a0cd55283b4e63fd92804da91c8d9896adcad9≥ c8efcc786146a951091588e5fa7e3c754850cb3c and < 1baff47b81f94f9231c91236aa511420d0e266b9≥ 6.6.32 and < 6.6.157version 6.9 | Vulnerable | CVE Program (cve.org) e CISA ADP |
| Linux | Linux Kernel | ≥ 6.6.32 and < 6.7≥ 6.9 and < 6.18.33≥ 6.19 and < 7.0.10 | 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 |
|---|---|---|---|---|---|
| 9.8 | CVSS 3.1 | Critical | 3.9 | 5.9 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 via NIST National Vulnerability Database |
| 9.8 | CVSS 3.1 | Critical | — | — | Linux via CVE Program (cve.org) e CISA ADP |
CVSS:3.1/AV:N/AC:L/PR:N/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 0.44%
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.
Analysis and videos
CVE-2026-53010: Linux kernel ksmbd use-after-free in smb2_open durable reconnect
CVE-2026-53010 is a use-after-free (CWE-416) in the ksmbd SMB server of the Linux kernel, triggered when a durable reconnect releases a file descriptor reference too early in smb2_open. The CNA assigned a CVSS 3.1 base score of 9.8 (critical), with a network attack vector and no privileges or user interaction required. The sources consulted show no confirmed exploitation.
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · linux/linux
- Record published
- Fix documented
- CVSS changed · 9.8
- 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
5 on the record
- git.kernel.org/stable/c/1baff47b81f94f9231c91236aa511420d0e266b9
- git.kernel.org/stable/c/ce2e164c1c51c3f7813b80f8c926836e896bcbb3
- git.kernel.org/stable/c/97a0cd55283b4e63fd92804da91c8d9896adcad9
- git.kernel.org/stable/c/f0ff7f12398e85b3a11745ff7feab6246f3d75c2
- git.kernel.org/stable/c/4db3dcac84c2f14a45ae201efb38de1fb1bfc009
Elsewhere on this site
Related CVEs (same products)
- Critical CVE-2026-99999 ipv4: validate checksum_start before completing checksum 6h
- Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 6h
- 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-2026-53010 is "Linux kernel ksmbd use-after-free in smb2_open durable reconnect", rated Critical. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 9.8 describes technical severity. EPSS 0.44% 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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