{"id":"CVE-2024-49883","url":"https://www.cyber-defence.io/tools/cve/CVE-2024-49883","generatedAt":"2026-10-28T02:16:23.440Z","title":"In the Linux kernel, the following vulnerability has been resolved: ext4: aovid use-after-free in ext4_ext_insert_extent() As Ojaswin mentioned in Link, in ext4_ext_insert_extent(), if the path is reallocated in ext4_ext_create_new_leaf(), we'll use the…","description":"In the Linux kernel, the following vulnerability has been resolved:\n\next4: aovid use-after-free in ext4_ext_insert_extent()\n\nAs Ojaswin mentioned in Link, in ext4_ext_insert_extent(), if the path is\nreallocated in ext4_ext_create_new_leaf(), we'll use the stale path and\ncause UAF. Below is a sample trace with dummy values:\n\next4_ext_insert_extent\n  path = *ppath = 2000\n  ext4_ext_create_new_leaf(ppath)\n    ext4_find_extent(ppath)\n      path = *ppath = 2000\n      if (depth > path[0].p_maxdepth)\n            kfree(path = 2000);\n            *ppath = path = NULL;\n      path = kcalloc() = 3000\n      *ppath = 3000;\n      return path;\n  /* here path is still 2000, UAF! */\n  eh = path[depth].p_hdr\n\n==================================================================\nBUG: KASAN: slab-use-after-free in ext4_ext_insert_extent+0x26d4/0x3330\nRead of size 8 at addr ffff8881027bf7d0 by task kworker/u36:1/179\nCPU: 3 UID: 0 PID: 179 Comm: kworker/u6:1 Not tainted 6.11.0-rc2-dirty #866\nCall Trace:\n <TASK>\n ext4_ext_insert_extent+0x26d4/0x3330\n ext4_ext_map_blocks+0xe22/0x2d40\n ext4_map_blocks+0x71e/0x1700\n ext4_do_writepages+0x1290/0x2800\n[...]\n\nAllocated by task 179:\n ext4_find_extent+0x81c/0x1f70\n ext4_ext_map_blocks+0x146/0x2d40\n ext4_map_blocks+0x71e/0x1700\n ext4_do_writepages+0x1290/0x2800\n ext4_writepages+0x26d/0x4e0\n do_writepages+0x175/0x700\n[...]\n\nFreed by task 179:\n kfree+0xcb/0x240\n ext4_find_extent+0x7c0/0x1f70\n ext4_ext_insert_extent+0xa26/0x3330\n ext4_ext_map_blocks+0xe22/0x2d40\n ext4_map_blocks+0x71e/0x1700\n ext4_do_writepages+0x1290/0x2800\n ext4_writepages+0x26d/0x4e0\n do_writepages+0x175/0x700\n[...]\n==================================================================\n\nSo use *ppath to update the path to avoid the above problem.","published":"2024-10-21T18:15:11.000Z","lastModified":"2026-08-04T11:20:56.000Z","status":"Modified","sourceIdentifier":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","cvss":{"version":"3.1","score":7.8,"severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"},"cwe":["CWE-416"],"affected":["debian/debian linux","linux/linux kernel"],"epss":{"score":0.00278,"percentile":0.20086,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.28%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://git.kernel.org/stable/c/51db04892a993cace63415be99848970a0f15ef2","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/5e811066c5ab709b070659197dccfb80ab650ddd","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/8162ee5d94b8c0351be0a9321be134872a7654a1","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/975ca06f3fd154c5f7742083e7b2574c57d1c0c3","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/9df59009dfc6d9fc1bd9ddf6c5ab6e56d6ed887a","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/a164f3a432aae62ca23d03e6d926b122ee5b860d","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/beb7b66fb489041c50c6473100b383f7a51648fc","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/bfed082ce4b1ce6349b05c09a0fa4f3da35ecb1b","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/e17ebe4fdd7665c93ae9459ba40fcdfb76769ac1","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html","tags":["Mailing List","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2025/03/msg00002.html","tags":["Mailing List","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2024-49883","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}