CVE-2026-68416 json
mtd: fix double free and WARN_ON in add_mtd_device() error paths
published 2026-08-10 2 mo ago modified 2026-11-06 2 d ago also EUVD-2026-55602
- cvss
- —
- not scored
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 5%
- public exploits
- 0
- none known
Summary
In the Linux kernel, the following vulnerability has been resolved:
mtd: fix double free and WARN_ON in add_mtd_device() error paths
When device_register() or mtd_nvmem_add() fails inside add_mtd_device() for a partition, the error handling triggers mtd_release() via put_device() or device_unregister(). mtd_release() calls release_mtd_partition() which frees the mtd_info structure. However, callers such as mtd_add_partition() and add_mtd_partitions() also call free_partition() in their error paths, resulting in a double free.
Additionally, release_mtd_partition() hits WARN_ON(!list_empty( &mtd->part.node)) because the partition node is still linked in the parent's partitions list when the release callback fires from the add_mtd_device() error path.
Fix this by overriding dev->type and dev->release before put_device() in the error paths, so that device_release() invokes a no-op function instead of mtd_release(). For the mtd_nvmem_add() failure case, device_unregister() is replaced with device_del() to separate the device removal from the final kobject reference drop, allowing the override to take effect before put_device() is called.
The callers' error paths (list_del + free_partition) remain the sole owners of mtd_info lifetime on add_mtd_device() failure, which is the expected contract.
The normal partition teardown path is not affected: del_mtd_device() goes through kref_put() -> mtd_device_release() -> device_unregister() with dev->type still set to &mtd_devtype, so mtd_release() -> release_mtd_partition() continues to work correctly for the regular removal case.
Patch / fix
- Linux Linux 6.6.148, 6.12.101, 6.18.42, 7.1.6, 7.2
- linux Debian 13 6.12.101-1
- linux Debian 14 7.1.6-1
- linux-6.12 Debian 12 6.12.101-1~deb12u1
debian advisories DEBIAN-CVE-2026-68416
- linux Ubuntu 24.04 LTS 6.8.0-147.147
- linux Ubuntu 26.04 LTS 7.0.0-38.38
- linux-aws Ubuntu 24.04 LTS 6.8.0-1067.70
- linux-aws Ubuntu 26.04 LTS 7.0.0-1014.14
- linux-gcp Ubuntu 24.04 LTS 6.8.0-1071.79
- linux-gcp Ubuntu 26.04 LTS 7.0.0-1014.14
- linux-gke Ubuntu 24.04 LTS 6.8.0-1066.74
- linux-gke Ubuntu 26.04 LTS 7.0.0-1008.9
ubuntu advisories UBUNTU-CVE-2026-68416
Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0
- kernel-rt Linux Micro 6.2 6.12.0-160000.38.1
- kernel-64kb SLES 16.0, Linux Micro 6.2, SLES for SAP applications 16.0 6.12.0-160000.38.1
- kernel-source SLES 16.0, Linux Micro 6.2, SLES for SAP applications 16.0 6.12.0-160000.38.1
- kernel-default SLES 16.0, SLE High Availability Extension 16.0, Linux Micro 6.2 +1 more 6.12.0-160000.38.1
- kernel-default-base SLES 16.0, Linux Micro 6.2, SLES for SAP applications 16.0 6.12.0-160000.38.1.160000.2.23
- kernel-syms SLES 16.0, Linux Micro Extras 6.2, SLES for SAP applications 16.0 6.12.0-160000.38.1
- kernel-azure SLES for SAP applications 16.0, SLES 16.0 6.12.0-160000.38.1
- kernel-obs-qa SLES for SAP applications 16.0, SLES 16.0 6.12.0-160000.38.1
suse advisories SUSE-SU-2026:23887-1SUSE-SU-2026:23902-1SUSE-SU-2026:23897-1SUSE-SU-2026:23881-1
- kernel-rt openSUSE Leap 16.0 6.12.0-160000.38.1
- dtb-aarch64 openSUSE Leap 16.0 6.12.0-160000.38.1
- kernel-64kb openSUSE Leap 16.0 6.12.0-160000.38.1
- kernel-syms openSUSE Leap 16.0 6.12.0-160000.38.1
- kernel-azure openSUSE Leap 16.0 6.12.0-160000.38.1
- kernel-obs-qa openSUSE Leap 16.0 6.12.0-160000.38.1
- kernel-source openSUSE Leap 16.0 6.12.0-160000.38.1
- kernel-default openSUSE Leap 16.0 6.12.0-160000.38.1
opensuse advisories openSUSE-SU-2026:21910-1
- git.kernel.org/stable/c/b1f78dc4a6869e30ff64345a5d3e7da1b6da0061 commit
- git.kernel.org/stable/c/1dfe90daee6080b088b65620ff690a56f59ddea2 commit
- git.kernel.org/stable/c/ffe21a3545b439e7b11578a701c22a847c149561 commit
- git.kernel.org/stable/c/e1e96aca1bdf391e2f49531c270ffc134e5b49a5 commit
- git.kernel.org/stable/c/f98ae09c727dcf34f745c875661c64b642e4abfa commit
- git.kernel.org/stable/c/820f983d641937a787e841ee4b93501f69f5683e commit
- git.kernel.org/stable/c/9d4af746af8ce27eefc2338b2feaa1e01f28b6c3 commit
Vendor advisories
What the vendors themselves say about their products: affected, fixed or not affected, and what to do.
red hat product security vex CVE-2026-68416 updated cvss 5.5
kernel: mtd: fix double free and WARN_ON in add_mtd_device() error paths
-
Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 moreaffected: workaround, no fix planned “Out of support scope”
-
Red Hat Enterprise Linux 10 kernelaffected: workaround, no fix available “Fix deferred”
-
Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +8 more Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-rt, kernel-core, kernel-tools, +29 more Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +83 morenot affected: vulnerable code not present
Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 2 d ago
Exploit prediction
0.16% chance of exploitation in the next 30 days, higher than 5% of all scored CVEs (FIRST EPSS, 2026-11-08).
Affected products
- Linux Linux
Classification
- Technology feeds
References
- git.kernel.org /stable/c/b1f78dc4a6869e30ff64345a5d3e7da1b6da0061
- git.kernel.org /stable/c/1dfe90daee6080b088b65620ff690a56f59ddea2
- git.kernel.org /stable/c/ffe21a3545b439e7b11578a701c22a847c149561
- git.kernel.org /stable/c/e1e96aca1bdf391e2f49531c270ffc134e5b49a5
- git.kernel.org /stable/c/f98ae09c727dcf34f745c875661c64b642e4abfa
- git.kernel.org /stable/c/820f983d641937a787e841ee4b93501f69f5683e
- git.kernel.org /stable/c/9d4af746af8ce27eefc2338b2feaa1e01f28b6c3
Sources
- CVE List CVE-2026-68416
- NVD CVE-2026-68416
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.