CVE-2024-49881: linux NULL Pointer Dereference
Vulnerability summary
CVE-2024-49881 is a medium (CVSS 5.5) NULL Pointer Dereference vulnerability in linux. EPSS estimates a 0.25% chance of exploitation in the next 30 days, higher than 15.2% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 40 · Related 37Timeline
- 21-10-2024PublishedVulnerability first disclosed.
- 15-10-2026Last modifiedVulnerability information updated.
Description
In the Linux kernel, the following vulnerability has been resolved: ext4: update orig_path in ext4_find_extent() In ext4_find_extent(), if the path is not big enough, we free it and set *orig_path to NULL. But after reallocating and successfully initializing the path, we don't update *orig_path, in which case the caller gets a valid path but a NULL ppath, and this may cause a NULL pointer dereference or a path memory leak. For example: ext4_split_extent path = *ppath = 2000 ext4_find_extent if (depth > path[0].p_maxdepth) kfree(path = 2000); *orig_path = path = NULL; path = kcalloc() = 3000 ext4_split_extent_at(*ppath = NULL) path = *ppath; ex = path[depth].p_ext; // NULL pointer dereference! ================================================================== BUG: kernel NULL pointer dereference, address: 0000000000000010 CPU: 6 UID: 0 PID: 576 Comm: fsstress Not tainted 6.11.0-rc2-dirty #847 RIP: 0010:ext4_split_extent_at+0x6d/0x560 Call Trace: <TASK> ext4_split_extent.isra.0+0xcb/0x1b0 ext4_ext_convert_to_initialized+0x168/0x6c0 ext4_ext_handle_unwritten_extents+0x325/0x4d0 ext4_ext_map_blocks+0x520/0xdb0 ext4_map_blocks+0x2b0/0x690 ext4_iomap_begin+0x20e/0x2c0 [...] ================================================================== Therefore, *orig_path is updated when the extent lookup succeeds, so that the caller can safely use path or *ppath.
CVSS metrics
3 scores · 3 sources · 1 version- OSV · UbuntuEcosystem advisory · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
0.25%
Chance of exploitation in the next 30 days
Percentile
15%
Versus all other CVEs
30-day change
0.00 pp
From 0.25% on 19-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Ubuntu134 products
- linuxAll versions (No fix recorded) | < 5.15.0-127.137 | < 6.8.0-54.56
- linux-allwinner-5.19All versions (No fix recorded)
- linux-awsAll versions (No fix recorded) | < 5.15.0-1073.79 | < 6.8.0-1023.25
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.11All versions (No fix recorded)
Linux2 products
- linux≥ 10809df84a4d868db61af621bae3658494165279, < ec0c0beb9b777cdd1edd7df9b36e0f3e67e2bdff | ≥ 10809df84a4d868db61af621bae3658494165279, < 6766937d0327000ac1b87c97bbecdd28b0dd6599 | ≥ 10809df84a4d868db61af621bae3658494165279, < a9fcb1717d75061d3653ed69365c8d45331815cd | ≥ 10809df84a4d868db61af621bae3658494165279, < 6801ed1298204d16a38571091e31178bfdc3c679 | ≥ 10809df84a4d868db61af621bae3658494165279, < f55ecc58d07a6c1f6d6d5b5af125c25f8da0bda2 | ≥ 10809df84a4d868db61af621bae3658494165279, < b63481b3a388ee2df9e295f97273226140422a42 | ≥ 10809df84a4d868db61af621bae3658494165279, < 11b230100d6801c014fab2afabc8bdea304c1b96 | ≥ 10809df84a4d868db61af621bae3658494165279, < 5b4b2dcace35f618fe361a87bae6f0d13af31bc1 | 3.18
- linux_kernel≥ 3.18, < 5.10.227 | ≥ 5.11, < 5.15.168 | ≥ 5.16, < 6.1.113 | ≥ 6.2, < 6.6.55 | ≥ 6.7, < 6.10.14 | ≥ 6.11, < 6.11.3
Debian1 product
- linux< 6.1.115-1 | < 6.11.4-1
3 vendors · 137 products
