CVE-2026-64384: smb: client: fix change notify replay double-free
Vulnerability summary
CVE-2026-64384 is a critical (CVSS 9.8) Double Free vulnerability in linux. EPSS estimates a 0.46% chance of exploitation in the next 30 days, higher than 38.6% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 29 · Related 27Timeline
- 25-07-2026PublishedVulnerability first disclosed.
- 19-10-2026Last modifiedVulnerability information updated.
Description
In the Linux kernel, the following vulnerability has been resolved: smb: client: fix change notify replay double-free A response-bearing attempt can return a replayable error and free its response buffer. If SMB2_notify_init() fails before the next send, cleanup retains the previous buffer type and frees that response again. Reset response bookkeeping before each attempt to prevent the stale free.
CVSS metrics
4 scores · 4 sources · 1 version- OSV · UbuntuEcosystem advisory · calculated9.8CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- OSV · DebianEcosystem advisory · calculated9.8CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- NVDNIST9.8CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS trend
Probability
0.46%
Chance of exploitation in the next 30 days
Percentile
39%
Versus all other CVEs
30-day change
No change 0.00 pp
From 0.46% on 22-09-2026
Known exploited
Compare KEV catalogsNot in the CISA KEV catalog.
Not in the ENISA CNW catalog.
Not in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Ubuntu142 products
- linuxAll versions (No fix recorded) | < 6.8.0-147.147 | < 7.0.0-31.31
- linux-allwinner-5.19All versions (No fix recorded)
- linux-awsAll versions (No fix recorded) | < 6.8.0-1067.70 | < 7.0.0-1012.12
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.11All versions (No fix recorded)
Debian2 products
- linux< 6.12.96-1 | < 7.1.4-1
- linux-6.12< 6.12.100-1~deb12u1
Linux2 products
- linux≥ 433042a91f9373241307725b52de573933ffedbf, < 5821f9dbb8b5b24391850a13418e633edd0fb003 | ≥ 4f1fffa2376922f3d1d506e49c0fd445b023a28e, < d684f4134998085702009b94c35c2003fc9e72d3 | ≥ 4f1fffa2376922f3d1d506e49c0fd445b023a28e, < 52af1975f0dfae990c5a0e85872cc41be0e88a68 | ≥ 4f1fffa2376922f3d1d506e49c0fd445b023a28e, < 901891513951bc8322ece754863909ea45af95c6 | ≥ 4f1fffa2376922f3d1d506e49c0fd445b023a28e, < 145f820dcbb2cced374f2532f8a61a44dce4a615 | ≥ 6.6.32, < 6.6.145 | 6.8
- linux_kernelEOL≥ 6.6.32, < 6.6.145 | ≥ 6.8.1, < 6.12.96 | ≥ 6.13, < 6.18.39 | ≥ 6.19, < 7.1.4 | 6.8 | 6.8:rc2 | 6.8:rc3 | 6.8:rc4 | 6.8:rc5 | 6.8:rc6 | 6.8:rc7
3 vendors · 146 products