CVE-2026-64192
What it is
In the Linux kernel, the following vulnerability has been resolved: bpf: Reject BPF_MAP_TYPE_INODE_STORAGE creation if BPF LSM is uninitialized When CONFIG_BPF_LSM=y is set, BPF inode storage maps (BPF_MAP_TYPE_INODE_STORAGE) are compiled into the kernel. However, if the BPF LSM is not explicitly enabled at boot time (e.g. omitted from the "lsm=" boot parameter), lsm_prepare() is never executed for the BPF LSM. Consequently, the BPF inode security blob offset (bpf_lsm_blob_sizes.lbs_inode) is never initialized and remains at its default compiled size of 8 bytes instead of being updated to a valid offset past the reserved struct rcu_head (typically 16 bytes or more). When a privileged user creates and updates a BPF_MAP_TYPE_INODE_STORAGE map, bpf_inode() evaluates inode->i_security + 8. This erroneously aliases the struct rcu_head.func callback pointer at the beginning of the inode->i_security blob. During subsequent map element cleanup or inode destruction, writing NULL to owner_storage clears the queued RCU callback pointer. When rcu_do_batch() later executes the queued callback, it attempts an instruction fetch at address 0x0, triggering an immediate kernel panic. Fix this by introducing a global bpf_lsm_initialized boolean flag marked with __ro_after_init. Set this flag to true inside bpf_lsm_init() when the LSM framework successfully registers the BPF LSM. Gate map allocation in inode_storage_map_alloc() on this flag, returning -EOPNOTSUPP if the BPF LSM is in turn uninitialized. This fail-fast approach prevents userspace from allocating inode storage maps when the supporting BPF LSM infrastructure is absent, avoiding zombie map states.
At a glance
- Exploitability
- Can be exploited locally on the machine with a low-privilege account. High risk of service disruption.
- Exploit odds
- 0.1% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.1% in the next 30 days (EPSS).
- Severity: 5.5 MEDIUM (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.1% · EPSS, next 30 days
- Weakness
- CWE-476 · NULL pointer dereference
- Record status
- Modified
Affected
- Linux Kernel < 6.6.148
- Linux Kernel < 6.12.97
- Linux Kernel < 6.18.40
- Linux Kernel < 7.1.4
- Linux Kernel 7.2
Attack profile CVSS 3.1 · 5.5
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-64192.md and follow it. Check whether this project is affected by CVE-2026-64192. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://git.kernel.org/stable/c/267fdd9b6530c399dfd996e1a0a7628b45baf9f0
- https://git.kernel.org/stable/c/5337eebdf8c5d4810b1913047f078d2815d5645f
- https://git.kernel.org/stable/c/a6f0643e4f63cfaa0d5d4a69de4f132eac4b8fe4
- https://git.kernel.org/stable/c/c76b8abce575e0c6e4096957220b4515ed847d89
- https://git.kernel.org/stable/c/de984ea883405420fdc416ae8964b752df586970
References
- https://git.kernel.org/stable/c/267fdd9b6530c399dfd996e1a0a7628b45baf9f0
- https://git.kernel.org/stable/c/413b14b9623a2e6ee131c2b2152b304aeb04e378
- https://git.kernel.org/stable/c/5337eebdf8c5d4810b1913047f078d2815d5645f
- https://git.kernel.org/stable/c/721f669853bdbf46b475a81bb5d05d610f8c19de
- https://git.kernel.org/stable/c/a6d634f794c808a261eac7d5af023a7e06b9ecd8
- https://git.kernel.org/stable/c/a6f0643e4f63cfaa0d5d4a69de4f132eac4b8fe4
- https://git.kernel.org/stable/c/c76b8abce575e0c6e4096957220b4515ed847d89
- https://git.kernel.org/stable/c/de984ea883405420fdc416ae8964b752df586970