CVE-2021-47259
Last modified
CVE-2021-47259 is a high-severity vulnerability rated 7.8/10 on the CVSS scale. In the Linux kernel, the following vulnerability has been resolved: NFS: Fix use-after-free in nfs4_init_client() KASAN reports a use-after-free when attempting to mount two different exports through two different NICs that belong to the same server. Olga was able to hit this with kernels starting somewhere between 5.7 and 5.10, but I traced the patch that introduced the clear_bit() call to 4.13. So something must have changed in the refcounting of the clp pointer to make this call to nfs_put_client() the very last one.. EPSS estimates a 1.11% chance of exploitation in the next 30 days.
Description
In the Linux kernel, the following vulnerability has been resolved: NFS: Fix use-after-free in nfs4_init_client() KASAN reports a use-after-free when attempting to mount two different exports through two different NICs that belong to the same server. Olga was able to hit this with kernels starting somewhere between 5.7 and 5.10, but I traced the patch that introduced the clear_bit() call to 4.13. So something must have changed in the refcounting of the clp pointer to make this call to nfs_put_client() the very last one.
Metrics
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Weakness Enumeration
Affected Software
| Vendor | Product | Versions | Update |
|---|---|---|---|
| Linux | Linux Kernel | >= 4.13, < 4.14.237 | — |
| Linux | Linux Kernel | >= 4.15, < 4.19.195 | — |
| Linux | Linux Kernel | >= 4.20, < 5.4.126 | — |
| Linux | Linux Kernel | >= 5.5, < 5.10.44 | — |
| Linux | Linux Kernel | >= 5.11, < 5.12.11 | — |
| Linux | Linux Kernel | 5.13 | Rc1 |
References
Timeline
- Published
- Last Modified
- Status
- Modified
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