Linux: Double Free
CVE-2026-64382 is a high-severity double free vulnerability in Linux, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. The record lists versions 02bc2896bdc3e29362d6e40d404006944a159c25, 3196b5192f246df4272072f61a2f4a3e9967f55d, 14498ff5ce0f272ce0ef988721413e06b7038972 as the first without the flaw, so updating Linux to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.35% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Linux to 02bc2896bdc3e29362d6e40d404006944a159c25 or 3196b5192f246df4272072f61a2f4a3e9967f55d or 14498ff5ce0f272ce0ef988721413e06b7038972 or ff2d30927bc3bf3c629f0768d2068096e64ef5ce, whichever matches your release line, or a later version.
- Update Linux Kernel to 6.6.145 or 6.12.96 or 6.18.39 or 7.1.4, whichever matches your release line, or a later version.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
- Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | 433042a91f9373241307725b52de573933ffedbf up to, but not including, 02bc2896bdc3e29362d6e40d404006944a159c25; 4f1fffa2376922f3d1d506e49c0fd445b023a28e up to, but not including, 3196b5192f246df4272072f61a2f4a3e9967f55d; 4f1fffa2376922f3d1d506e49c0fd445b023a28e up to, but not including, 14498ff5ce0f272ce0ef988721413e06b7038972; 4f1fffa2376922f3d1d506e49c0fd445b023a28e up to, but not including, ff2d30927bc3bf3c629f0768d2068096e64ef5ce; 4f1fffa2376922f3d1d506e49c0fd445b023a28e up to, but not including, b55e182f2324bc6a604c21a47aa6c448f719a532; 6.6.32 up to, but not including, 6.6.145; 6.8 | 02bc2896bdc3e29362d6e40d404006944a159c25, 3196b5192f246df4272072f61a2f4a3e9967f55d, 14498ff5ce0f272ce0ef988721413e06b7038972, ff2d30927bc3bf3c629f0768d2068096e64ef5ce, b55e182f2324bc6a604c21a47aa6c448f719a532, 6.6.145 |
| Linux | Linux Kernel | 6.6.32 up to, but not including, 6.6.145; 6.8.1 up to, but not including, 6.12.96; 6.13 up to, but not including, 6.18.39; 6.19 up to, but not including, 7.1.4; 6.8 | 6.6.145, 6.12.96, 6.18.39, 7.1.4 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- RequiredA user must take an action such as opening a file or link.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H. Scored by CNA.
Official description
In the Linux kernel, the following vulnerability has been resolved: smb: client: fix double-free in SMB2_open() replay A response-bearing attempt can return a replayable error and free its response buffer. If SMB2_open_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.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Double Free
The product calls free() twice on the same memory address.
How developers prevent this class of flaw
- Choose a language that provides automatic memory management.
- Ensure that each allocation is freed only once. After freeing a chunk, set the pointer to NULL to ensure the pointer cannot be freed again. In complicated error conditions, be sure that clean-up routines respect the state of allocation properly. If the language is object oriented, ensure that object destructors delete each chunk of memory only once.
- Use a static analysis tool to find double free instances.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
- git.kernel.org/stable/c/02bc2896bdc3e29362d6e40d404006944a159c25
- git.kernel.org/stable/c/14498ff5ce0f272ce0ef988721413e06b7038972
- git.kernel.org/stable/c/3196b5192f246df4272072f61a2f4a3e9967f55d
- git.kernel.org/stable/c/b55e182f2324bc6a604c21a47aa6c448f719a532
- git.kernel.org/stable/c/ff2d30927bc3bf3c629f0768d2068096e64ef5ce
Recent Double Free vulnerabilities
- 7.8 High severity
- 9.8 Critical severity
- 9.8 Critical severity
- 9.8 Critical severity
- 9.8 Critical severity
- 9.8 Critical severity
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