Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
AV AC PR UI S C I A CVSS EPSS %ile KEV P L N N U N N H 4.6 .0016 6.1 —
AFFECTED Product Versions Fixed zephyr 3.5.0 – —
TIMELINE Apr 24 Reserved by zephyr Jul 24 EXPLOIT PUBLISHED — CVE-2026-7007 (zephyrproject zephyr). Public exploit reference added. Jul 24 Published (CNA: zephyr)
The Zephyr ext2 file system validates the on-disk superblock in ext2_verify_disk_superblock() (subsys/fs/ext2/ext2_impl.c) before completing a mount. The validator checked the magic number, block size, revision and feature flags, but did not verify that the on-disk fields s_blocks_per_group and s_inodes_per_group are non-zero. Both fields are read directly from the image and are later used as divisors during mount-time initialization. During mount, get_ngroups() divides and modulos s_blocks_count by s_blocks_per_group (reached via ext2_fetch_block_group() from ext2_init_fs()), and get_itable_entry() divides (ino - 1) by s_inodes_per_group when fetching the root inode (both in subsys/fs/ext2/ext2_diskops.c). A superblock with either field set to zero therefore causes an integer division by zero during the mount sequence. An attacker who can present a crafted ext2 image to a device that mounts ext2 — removable media such as an SD card or a USB mass-storage device — can trigger this. On ARMv7-M / ARMv8-M-mainline Cortex-M targets, divide-by-zero trapping is enabled (SCB_CCR_DIV_0_TRP), so the division raises a UsageFault that Zephyr treats as a fatal error, producing a denial of service. The impact is limited to availability; the malformed value is consumed only as a divisor. The fix rejects a zero s_blocks_per_group or s_inodes_per_group in the superblock validator, returning -EINVAL so the mount fails before any block-group or inode I/O occurs.
| Date | Event | Detail |
|---|---|---|
| April 24, 2026 | Reserved | Reserved by zephyr |
| July 24, 2026 | EXPLOIT PUBLISHED | EXPLOIT PUBLISHED — CVE-2026-7007 (zephyrproject zephyr). Public exploit reference added. |
| July 24, 2026 | Published | Published (CNA: zephyr) |
| Vendor | Product / Package | Ecosystem | Version introduced | Fixed |
|---|---|---|---|---|
| zephyrproject | zephyr | — | 3.5.0 | — |
Authoritative record: CVE-2026-7007 at cve.org
Vendors: zephyrproject
Weaknesses: CWE-369
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-7007 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.