Answer in brief
CVE-2026-98985 records a Unknown severity vulnerability in namespace: check the mounts before reading their parents in pivot_root(). The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=e0c9c0afd2fc958ffa34b697972721d81df8a56f <a56d4f8f8f4c5d9ac339d5c03a9d90eecd3697fc || >=e0c9c0afd2fc958ffa34b697972721d81df8a56f <3c2441e21c3df867e4131e0ff784ecdb3a7a55f8 || >=e0c9c0afd2fc958ffa34b697972721d81df8a56f <e3aba6900483f64e6c9eb328150dd633b7d36c1c || >=e0c9c0afd2fc958ffa34b697972721d81df8a56f <3dad2330c89343ba083cf7868779083fd5fbe0fe || >=e0c9c0afd2fc958ffa34b697972721d81df8a56f <6b7c001eb5857fa09041f47673666060a2e5fc1c || 84b78514033ff22c443473214ab6d0508394cf7a || >=4.0.2 <4.1 | a56d4f8f8f4c5d9ac339d5c03a9d90eecd3697fc, 3c2441e21c3df867e4131e0ff784ecdb3a7a55f8, e3aba6900483f64e6c9eb328150dd633b7d36c1c, 3dad2330c89343ba083cf7868779083fd5fbe0fe, 6b7c001eb5857fa09041f47673666060a2e5fc1c, 4.1 |
| Linux/Linuxgeneric | 4.1 | Not reported |
Published upstream
Oct 23, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 23, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Oct 23, 2026
In the Linux kernel, the following vulnerability has been resolved: namespace: check the mounts before reading their parents in pivot_root() path_pivot_root() reads the parents of new_root and of the caller's root and checks whether they are shared before it checks that either mount is in the caller's mount namespace. Only namespace_sem is held. That's fine for a mount that is in the caller's mount namespace. But new_root can be a file descriptor to a mount that has been unmounted and that only the file descriptor keeps alive. If that mount stayed attached to its parent when it was unmounted nothing pins the parent for it. The final mntput() of the parent unhooks the children under mount_lock alone and frees the parent afterwards: pivot_root() close(fd), last ref on the parent ------------ --------------------------------- ex_parent = new_mnt->mnt_parent mntput_no_expire_slowpath() __umount_mnt(new_mnt) cleanup_mnt() call_rcu() IS_MNT_SHARED(ex_parent) BUG: KASAN: slab-use-after-free in path_pivot_root+0xf1a/0x1840 Read of size 4 at addr ffff8881047382f8 by task pivot_widen/157 path_pivot_root+0xf1a/0x1840 __x64_sys_pivot_root+0x165/0x190 The same goes for the caller's root via chroot(). Both outcomes of the check end in EINVAL so nothing but the read itself goes wrong. It's the same thing commit bb4609405752 ("statmount: read the parent of an unmounted mount under mount_lock") fixed for statmount(). Check that both mounts are in the caller's namespace before their parents are read. Every path returns EINVAL either way.
Quoted source text, attributed separately from HOL analysis.