Linux: Use After Free
CVE-2026-53010 is a critical-severity use after free vulnerability in Linux, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists versions f0ff7f12398e85b3a11745ff7feab6246f3d75c2, 4db3dcac84c2f14a45ae201efb38de1fb1bfc009, ce2e164c1c51c3f7813b80f8c926836e896bcbb3 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 0.44% chance of exploitation within 30 days, which is low compared with other CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Update Linux to f0ff7f12398e85b3a11745ff7feab6246f3d75c2 or 4db3dcac84c2f14a45ae201efb38de1fb1bfc009 or ce2e164c1c51c3f7813b80f8c926836e896bcbb3 or 97a0cd55283b4e63fd92804da91c8d9896adcad9, whichever matches your release line, or a later version.
- Update Linux Kernel to 6.7 or 6.18.33 or 7.0.10, 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.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | 8df4bcdb0a4232192b2445256c39b787d58ef14d up to, but not including, f0ff7f12398e85b3a11745ff7feab6246f3d75c2; c8efcc786146a951091588e5fa7e3c754850cb3c up to, but not including, 4db3dcac84c2f14a45ae201efb38de1fb1bfc009; c8efcc786146a951091588e5fa7e3c754850cb3c up to, but not including, ce2e164c1c51c3f7813b80f8c926836e896bcbb3; c8efcc786146a951091588e5fa7e3c754850cb3c up to, but not including, 97a0cd55283b4e63fd92804da91c8d9896adcad9; c8efcc786146a951091588e5fa7e3c754850cb3c up to, but not including, 1baff47b81f94f9231c91236aa511420d0e266b9; 6.6.32 up to, but not including, 6.6.157; 6.9 | f0ff7f12398e85b3a11745ff7feab6246f3d75c2, 4db3dcac84c2f14a45ae201efb38de1fb1bfc009, ce2e164c1c51c3f7813b80f8c926836e896bcbb3, 97a0cd55283b4e63fd92804da91c8d9896adcad9, 1baff47b81f94f9231c91236aa511420d0e266b9, 6.6.157 |
| Linux | Linux Kernel | 6.6.32 up to, but not including, 6.7; 6.9 up to, but not including, 6.18.33; 6.19 up to, but not including, 7.0.10 | 6.7, 6.18.33, 7.0.10 |
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
- NoneNo action by a victim is required.
- 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:N/S:U/C:H/I:H/A:H. Scored by CNA.
Official description
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.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Use After Free
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.
How developers prevent this class of flaw
- Choose a language that provides automatic memory management.
- When freeing pointers, be sure to set them to NULL once they are freed. However, the utilization of multiple or complex data structures may lower the usefulness of this strategy.
Timeline
- CVE record published.
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
Other references
Recent Use After Free vulnerabilities
- 7.5 High severity
- 8.8 High severity
- 7.8 High severity
- 8.8 High severity
- 8.8 High severity
- 9.6 Critical severity
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