imPC@ndo IT

Tracker / CVE-2021-47259

CVE-2021-47259

High 7.8

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.

Affected products and versions

linux linux_kernel
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 · 5.11 → 5.12.11
linux linux_kernel · 5.5 → 5.10.44

Analysis

This page is not indexable yet.Until it carries original analysis — what it actually exposes, how to check in two minutes whether a system was touched, what to do if it was — the page stays noindex. The database decides that, not the template.

References