In the Linux kernel, the following vulnerability has been resolved:
fs: preserve ACL_DONT_CACHE state in forget_cached_acl()
The ACL_DONT_CACHE state is meant to be a constant state for the inode for filesystems that want to opt out of posix acl caching.
Commit facd61053cff1 ("fuse: fixes after adapting to new posix acl api") used this facility to opt out of posix acl caching for fuse inodes with fuse server that does not negotiate FUSE_POSIX_ACL (fc->posix_acl).
The commit also takes care to gate the forget_all_cached_acls() call in fuse_set_acl() on fc->posix_acl because there is no need for it, but there are other placed in fuse code which call forget_all_cached_acls() unconditional to fc->posix_acl and those cause the loss of the ACL_DONT_CACHE state.
This is not only a functional bug. Properly timed, a get_acl() from this fuse filesystem can return a stale cached value, as was observed in tests, because set_acl() does not invalidate the unintentional acl cache.
We could fix this in fuse, but it actually makes no sense for the vfs helper forget_cached_acl() to invalidate the ACL_DONT_CACHE state, so let it not do that to fix fuse and future users of ACL_DONT_CACHE.
CVSS Details
- CVSS 3.1 Base Score: 8.4
- CVSS 3.1 Vector: (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Amazon_linux_2023 | — | Upgrade kernel6.12-develUpgrade kernel6.12-tools-debuginfoUpgrade kernel6.12-modules-extra-commonUpgrade kernel6.12-tools-develUpgrade python3-perf6.12-debuginfoUpgrade perf6.12-debuginfoUpgrade kernel6.12-debuginfoUpgrade kernel6.12-modules-extraUpgrade python3-perf6.12Upgrade kernel6.12-toolsUpgrade kernel6.12-debuginfo-common-aarch64Upgrade kernel6.12-debuginfo-common-x86_64Upgrade bpftool6.12-debuginfoUpgrade perf6.12Upgrade kernel-livepatch-6.12.103-127.188Upgrade bpftool6.12Upgrade kernel6.12Upgrade kernel6.12-headers | Sep 1, 2026 | Aug 10, 2026 |
| Debian | — | Upgrade linux-6.12Upgrade linux | Aug 11, 2026 | Aug 11, 2026 |
| Redhat_linux | — | No solution exists | Aug 17, 2026 | Aug 10, 2026 |
| Vmware Photon_os | — | Use 'tdnf update' to upgrade all packages to the latest version. | Aug 17, 2026 | Aug 10, 2026 |
Prioritise with Active Threat Intelligence
With curated Threat Intelligence, you can see which vulnerabilities truly put you at risk, prioritize what matters most, and act before attackers do.
Explore Intelligence Hub