CVE-2024-49883ext4: aovid use-after-free in ext4_ext_insert_extent()
- 7.8HighCVSS base score
- 0.28%Exploitation in 30 daysEPSS · top 80% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
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 stale path and cause UAF. Below is a sample trace with dummy values: ext4_ext_insert_extent path = *ppath = 2000 ext4_ext_create_new_leaf(ppath) ext4_find_extent(ppath) path = *ppath = 2000 if (depth > path[0].p_maxdepth) kfree(path = 2000); *ppath = path = NULL; path = kcalloc() = 3000 *ppath = 3000; return path; /* here path is still 2000, UAF! */ eh = path[depth].p_hdr ================================================================== BUG: KASAN: slab-use-after-free in ext4_ext_insert_extent+0x26d4/0x3330 Read of size 8 at addr ffff8881027bf7d0 by task kworker/u36:1/179 CPU: 3 UID: 0 PID: 179 Comm: kworker/u6:1 Not tainted 6.11.0-rc2-dirty #866 Call Trace: <TASK> ext4_ext_insert_extent+0x26d4/0x3330 ext4_ext_map_blocks+0xe22/0x2d40 ext4_map_blocks+0x71e/0x1700 ext4_do_writepages+0x1290/0x2800 [...] Allocated by task 179: ext4_find_extent+0x81c/0x1f70 ext4_ext_map_blocks+0x146/0x2d40 ext4_map_blocks+0x71e/0x1700 ext4_do_writepages+0x1290/0x2800 ext4_writepages+0x26d/0x4e0 do_writepages+0x175/0x700 [...] Freed by task 179: kfree+0xcb/0x240 ext4_find_extent+0x7c0/0x1f70 ext4_ext_insert_extent+0xa26/0x3330 ext4_ext_map_blocks+0xe22/0x2d40 ext4_map_blocks+0x71e/0x1700 ext4_do_writepages+0x1290/0x2800 ext4_writepages+0x26d/0x4e0 do_writepages+0x175/0x700 [...] ================================================================== So use *ppath to update the path to avoid the above problem.
Timeline
ID reserved
By Linux
Published
- 22 months later
· 22 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| LinuxCNA (assigner) | 3.1 | High7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Modified | 3.1 | High7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.28% · top 80% of all CVEs (12 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.8.
Affected products
- affected 10809df84a4d868db61af621bae3658494165279 – < e17ebe4fdd7665c93ae9459ba40fcdfb76769ac1
- affected 10809df84a4d868db61af621bae3658494165279 – < 975ca06f3fd154c5f7742083e7b2574c57d1c0c3
- affected 10809df84a4d868db61af621bae3658494165279 – < 5e811066c5ab709b070659197dccfb80ab650ddd
- affected 10809df84a4d868db61af621bae3658494165279 – < 9df59009dfc6d9fc1bd9ddf6c5ab6e56d6ed887a
- affected 10809df84a4d868db61af621bae3658494165279 – < 51db04892a993cace63415be99848970a0f15ef2
- affected 10809df84a4d868db61af621bae3658494165279 – < 8162ee5d94b8c0351be0a9321be134872a7654a1
- affected 10809df84a4d868db61af621bae3658494165279 – < beb7b66fb489041c50c6473100b383f7a51648fc
- affected 10809df84a4d868db61af621bae3658494165279 – < bfed082ce4b1ce6349b05c09a0fa4f3da35ecb1b
- affected 10809df84a4d868db61af621bae3658494165279 – < a164f3a432aae62ca23d03e6d926b122ee5b860d
- affected 3.18
- unaffected < 3.18
- unaffected 4.19.323 – ≤ 4.19.*
- unaffected 5.4.285 – ≤ 5.4.*
- unaffected 5.10.227 – ≤ 5.10.*
- unaffected 5.15.168 – ≤ 5.15.*
- unaffected 6.1.113 – ≤ 6.1.*
- unaffected 6.6.55 – ≤ 6.6.*
- unaffected 6.10.14 – ≤ 6.10.*
- unaffected 6.11.3 – ≤ 6.11.*
- unaffected 6.12 – ≤ *
References
References11
- https://git.kernel.org/stable/c/e17ebe4fdd7665c93ae9459ba40fcdfb76769ac1 (opens in a new tab)
- https://git.kernel.org/stable/c/975ca06f3fd154c5f7742083e7b2574c57d1c0c3 (opens in a new tab)
- https://git.kernel.org/stable/c/5e811066c5ab709b070659197dccfb80ab650ddd (opens in a new tab)
- https://git.kernel.org/stable/c/9df59009dfc6d9fc1bd9ddf6c5ab6e56d6ed887a (opens in a new tab)
- https://git.kernel.org/stable/c/51db04892a993cace63415be99848970a0f15ef2 (opens in a new tab)
- https://git.kernel.org/stable/c/8162ee5d94b8c0351be0a9321be134872a7654a1 (opens in a new tab)
- https://git.kernel.org/stable/c/beb7b66fb489041c50c6473100b383f7a51648fc (opens in a new tab)
- https://git.kernel.org/stable/c/bfed082ce4b1ce6349b05c09a0fa4f3da35ecb1b (opens in a new tab)
- https://git.kernel.org/stable/c/a164f3a432aae62ca23d03e6d926b122ee5b860d (opens in a new tab)
- https://lists.debian.org/debian-lts-announce/2025/03/msg00002.html (opens in a new tab)
- https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2024-43583 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2024-49883)Record last updated .