{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2026-23238 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-23238 is a medium-severity vulnerability in Linux kernel, published on 4 Mar 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-2026-23238 and fix it if it is affected.\n\nWhat it is: CVE-2026-23238 is a medium-severity vulnerability in Linux kernel, published on 4 Mar 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-2026-23238 in the wild and no public exploit code.\n\nAffected product: Linux kernel. 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-2026-23238/ (Markdown: https://insights.sbomify.com/CVE-2026-23238/index.md)","id":"CVE-2026-23238","markdown":"https://insights.sbomify.com/CVE-2026-23238/index.md","name":"CVE-2026-23238","record":{"aliases":["BELL-CVE-2026-23238","DEBIAN-CVE-2026-23238","GHSA-wj4m-w3qm-xpch","ROOT-OS-DEBIAN-11-CVE-2026-23238","ROOT-OS-DEBIAN-12-CVE-2026-23238","ROOT-OS-DEBIAN-13-CVE-2026-23238","ROOT-OS-UBUNTU-2204-CVE-2026-23238","ROOT-OS-UBUNTU-2404-CVE-2026-23238","UBUNTU-CVE-2026-23238"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":true,"product_category":"Linux kernel","requires_auth":"low_privilege","summary":"A local attacker can cause a kernel crash by mounting a romfs filesystem on a loop device with an incompatible block size, leading to denial of service.","user_interaction":"not_required","vuln_class":"null_dereference"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[{"product":"linux_kernel","vendor":"linux"}],"cvss":{"score":5.5,"severity":"medium","source":"nvd","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","version":"3.1"},"cwes":[{"id":"CWE-617","name":"Reachable Assertion"}],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nromfs: check sb_set_blocksize() return value\n\nromfs_fill_super() ignores the return value of sb_set_blocksize(), which\ncan fail if the requested block size is incompatible with the block\ndevice's configuration.\n\nThis can be triggered by setting a loop device's block size larger than\nPAGE_SIZE using ioctl(LOOP_SET_BLOCK_SIZE, 32768), then mounting a romfs\nfilesystem on that device.\n\nWhen sb_set_blocksize(sb, ROMBSIZE) is called with ROMBSIZE=4096 but the\ndevice has logical_block_size=32768, bdev_validate_blocksize() fails\nbecause the requested size is smaller than the device's logical block\nsize. sb_set_blocksize() returns 0 (failure), but romfs ignores this and\ncontinues mounting.\n\nThe superblock's block size remains at the device's logical block size\n(32768). Later, when sb_bread() attempts I/O with this oversized block\nsize, it triggers a kernel BUG in folio_set_bh():\n\n    kernel BUG at fs/buffer.c:1582!\n    BUG_ON(size \u003e PAGE_SIZE);\n\nFix by checking the return value of sb_set_blocksize() and failing the\nmount with -EINVAL if it returns 0.","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":"romfs: check sb_set_blocksize() return value","id":"CVE-2026-23238","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"null_dereference","year":"2026"},"n_packages":0,"n_references":7,"next":{"headline":"espintcp: Fix race condition in espintcp_close()","id":"CVE-2026-23239"},"packages":[],"prev":{"headline":"platform/x86: classmate-laptop: Add missing NULL pointer checks","id":"CVE-2026-23237"},"products":["Linux"],"published":"2026-03-04","related":[{"cvss_score":8.8,"headline":"Linux Kernel Out-of-Bounds Write","id":"CVE-2026-53266","kev_date_added":"2026-09-18","published":"2026-06-25"},{"cvss_score":8.8,"headline":"Linux Kernel Improper Input Validation","id":"CVE-2013-6282","kev_date_added":"2022-09-15","published":"2013-11-19"},{"cvss_score":8.4,"headline":"Linux Kernel Heap-Based Buffer Overflow","id":"CVE-2022-0185","kev_date_added":"2024-08-21","published":"2022-02-11"},{"cvss_score":8.4,"headline":"Linux Kernel Privilege Escalation","id":"CVE-2013-2094","kev_date_added":"2022-09-15","published":"2013-05-14"},{"cvss_score":7.8,"headline":"Linux Kernel Unspecified","id":"CVE-2026-53362","kev_date_added":"2026-08-27","published":"2026-07-04"},{"cvss_score":7.8,"headline":"Linux Kernel Missing Initialization of a Variable","id":"CVE-2026-46300","kev_date_added":"2026-10-28","published":"2026-05-23"},{"cvss_score":7.8,"headline":"Linux Kernel Race Condition","id":"CVE-2025-39964","kev_date_added":"2026-09-18","published":"2025-10-13"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"US public information, NVD API terms","name":"NVD"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2026-06-02","vendors":["Linux"]},"summary":"A local attacker can cause a kernel crash by mounting a romfs filesystem on a loop device with an incompatible block size, leading to denial of service.","url":"https://insights.sbomify.com/CVE-2026-23238/"}