{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-74307 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-74307 is a denial of service vulnerability in Linux, published on 15 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-74307 and fix it if it is affected.\n\nWhat it is: CVE-2026-74307 is a denial of service vulnerability in Linux, published on 15 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2026-74307 in the wild and no public exploit code.\n\nAffected product: Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2026-74307/ (Markdown: https://insights.sbomify.com/CVE-2026-74307/index.md)","id":"CVE-2026-74307","markdown":"https://insights.sbomify.com/CVE-2026-74307/index.md","name":"CVE-2026-74307","record":{"aliases":["AZL-96462","BELL-CVE-2026-74307","DEBIAN-CVE-2026-74307","GHSA-j6rh-x9jg-pr3v","UBUNTU-CVE-2026-74307"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Linux kernel","requires_auth":"low_privilege","summary":"A local attacker can cause a kernel deadlock in the ext4 filesystem by triggering a race condition with the EXT4_IOC_MOVE_EXT ioctl and a filesystem freeze.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[],"cvss":{"score":null,"severity":null,"source":null,"vector":null,"version":null},"cwes":[],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\next4: validate donor file superblock early in EXT4_IOC_MOVE_EXT\n\nReject the EXT4_IOC_MOVE_EXT ioctl early if the donor file does not\nbelong to the same superblock as the original file.  Currently, this\nvalidation is performed inside ext4_move_extents() by\nmext_check_validity(), but only after lock_two_nondirectories() has\nalready acquired the inode locks.  When the donor fd refers to a file\non a different filesystem (e.g., overlayfs), this late validation\ncreates a circular lock dependency:\n\n  CPU0 (overlayfs write)            CPU1 (ext4 ioctl)\n  ----                              ----\n  inode_lock(ovl_inode)\n                                    mnt_want_write_file(filp)\n                                      sb_start_write(ext4_sb)   [sb_writers]\n    backing_file_write_iter()\n      vfs_iter_write(real_file)\n        file_start_write(real_file)\n          sb_start_write(ext4_sb)   [blocked by freeze]\n                                    lock_two_nondirectories()\n                                      inode_lock(ovl_inode)     [blocked]\n\nWith a concurrent freeze operation holding sb_writers write side, this\nforms a deadlock cycle: CPU0 waits for freeze to complete, freeze waits\nfor CPU1's sb_writers reader to exit, CPU1 waits for CPU0's inode lock.\n\nSince EXT4_IOC_MOVE_EXT exchanges physical extents between two files,\nit fundamentally requires both files to reside on the same ext4\nfilesystem.  Moving the superblock check before any lock acquisition\nis both semantically correct and eliminates the circular dependency\nby ensuring that cross-filesystem donor fds are rejected before\nsb_writers or inode locks are taken.","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":true,"headline":"ext4: validate donor file superblock early in EXT4_IOC_MOVE_EXT","id":"CVE-2026-74307","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"denial_of_service","year":"2026"},"n_packages":0,"n_references":5,"next":{"headline":"ext4: fix kernel BUG in ext4_write_inline_data_end","id":"CVE-2026-74308"},"packages":[],"prev":{"headline":"vfio/qat: fix f_pos race in qat_vf_resume_write()","id":"CVE-2026-74306"},"products":["Linux"],"published":"2026-08-15","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2026-10-21","vendors":["Linux"]},"summary":"A local attacker can cause a kernel deadlock in the ext4 filesystem by triggering a race condition with the EXT4_IOC_MOVE_EXT ioctl and a filesystem freeze.","url":"https://insights.sbomify.com/CVE-2026-74307/"}