CVE-2026-74307: linux

CVSS: UnknownReceived
AliasesUBUNTU-CVE-2026-74307DEBIAN-CVE-2026-74307
Published 15-08-2026Last modified 21-10-2026
Open JSON

Vulnerability summary

CVE-2026-74307 is a vulnerability in linux with no CVSS score yet. EPSS estimates a 0.17% chance of exploitation in the next 30 days, higher than 5.7% of scored vulnerabilities.

Overall risk
0/100
0100
Minimal · default modelHow is this calculated?
CVSS score
Not scored
010
No CVSS score recorded
EPSS score
0.17%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 18 · Related 18
OPENSUSE-SU-2026:21910-1SUSE-SU-2026:23881-1SUSE-SU-2026:23887-1SUSE-SU-2026:23897-1SUSE-SU-2026:23902-1SUSE-SU-2026:24181-1

Timeline

  1. 15-08-2026
    PublishedVulnerability first disclosed.
  2. 21-10-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: ext4: validate donor file superblock early in EXT4_IOC_MOVE_EXT Reject the EXT4_IOC_MOVE_EXT ioctl early if the donor file does not belong to the same superblock as the original file. Currently, this validation is performed inside ext4_move_extents() by mext_check_validity(), but only after lock_two_nondirectories() has already acquired the inode locks. When the donor fd refers to a file on a different filesystem (e.g., overlayfs), this late validation creates a circular lock dependency: CPU0 (overlayfs write) CPU1 (ext4 ioctl) ---- ---- inode_lock(ovl_inode) mnt_want_write_file(filp) sb_start_write(ext4_sb) [sb_writers] backing_file_write_iter() vfs_iter_write(real_file) file_start_write(real_file) sb_start_write(ext4_sb) [blocked by freeze] lock_two_nondirectories() inode_lock(ovl_inode) [blocked] With a concurrent freeze operation holding sb_writers write side, this forms a deadlock cycle: CPU0 waits for freeze to complete, freeze waits for CPU1's sb_writers reader to exit, CPU1 waits for CPU0's inode lock. Since EXT4_IOC_MOVE_EXT exchanges physical extents between two files, it fundamentally requires both files to reside on the same ext4 filesystem. Moving the superblock check before any lock acquisition is both semantically correct and eliminates the circular dependency by ensuring that cross-filesystem donor fds are rejected before sb_writers or inode locks are taken.

CVSS metrics

Risk metrics not yet published.

EPSS trend

Probability

0.17%

Chance of exploitation in the next 30 days

Percentile

6%

Versus all other CVEs

30-day change

0.00 pp

From 0.17% on 21-09-2026

21-09-202621-10-2026
EPSS score
0.17%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

No weakness data has been published for this record.

Affected systems

Ubuntu169 products
  • linuxAll versions (No fix recorded) | < 6.8.0-147.147 | < 7.0.0-38.38
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-awsAll versions (No fix recorded) | < 6.8.0-1067.70 | < 7.0.0-1014.14
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Debian1 product
  • linuxAll versions (No fix recorded) | < 6.12.100-1 | < 7.1.5-1
Linux1 product
  • linux≥ fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a, < 663f184b51492093d408e518efc95ee13b5b4440 | ≥ fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a, < 74796e886ca39fcb0d3fd36ea6a39c62784ab6fb | ≥ fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a, < 29e07ec352f0ad06c833a18bf47d82c81f55544f | ≥ fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a, < fb52013cad9e9b7d3a6a14ea1bcd841e41da7c6c | ≥ fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a, < c143957520c6c9b5cd72e0de8b52b814f0c576fe | 3.18

3 vendors · 171 products

References

17 links
Show all 17 references