Use After Free in Linux

CVE-2026-53388

In the Linux kernel, the following vulnerability has been resolved: fuse: re-lock request before replacing page cache folio fuse_try_move_folio() unlocks the request on entry but does not re-lock it on the success path. This means fuse_chan_abort() can end the request and free the fuse_io_args (eg fuse_readpages_end()) while the subsequent copy chain logic after fuse_try_move_folio() accesses the fuse_io_args, leading to use-after-free issues. Fix this by calling lock_request() before replace_page_cache_folio(). This ensures the request is locked on the success path which will prevent the fuse_io_args from being freed while the later copying logic runs, and also ensures that the ap->folios[i]->mapping is never null since ap->folios[i] will always point to the newfolio after replace_page_cache_folio().

Vulnerability class: Use-After-Free

EPSS: 0.001 (3.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-53388?
CVE-2026-53388 is a high-severity vulnerability in Linux, classified under Use After Free. CVSS score: 7.8/10. Published 2026-07-19.
How severe is CVE-2026-53388?
High severity. CVSS v3 base score is 7.8 out of 10.