Linux: Double Free
CVE-2024-46741 is a high-severity double free vulnerability in Linux, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists versions 4753cc37b6606ef9a7ec22861d380d45e2707f9a, f77dc8a75859e559f3238a6d906206259227985e, bfc1704d909dc9911a558b1a5833d3d61a43a1f2 as the first without the flaw, so updating Linux to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.24% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Linux to 4753cc37b6606ef9a7ec22861d380d45e2707f9a or f77dc8a75859e559f3238a6d906206259227985e or bfc1704d909dc9911a558b1a5833d3d61a43a1f2 or e8c276d4dc0e19ee48385f74426aebc855b49aaf, whichever matches your release line, or a later version.
- Update Linux Kernel to 6.6.51 or 6.10.10, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | 13327ed95222e70fa98805382b65636b872d87cb up to, but not including, 4753cc37b6606ef9a7ec22861d380d45e2707f9a; 72fa6f7820c4cf96c5f7aabc4e54bdf52d1e2ac2 up to, but not including, f77dc8a75859e559f3238a6d906206259227985e; 72fa6f7820c4cf96c5f7aabc4e54bdf52d1e2ac2 up to, but not including, bfc1704d909dc9911a558b1a5833d3d61a43a1f2; 72fa6f7820c4cf96c5f7aabc4e54bdf52d1e2ac2 up to, but not including, e8c276d4dc0e19ee48385f74426aebc855b49aaf; 911737ad0c860251f640a05feb75f9dc7e41f0d7; b10e064ca0f708c4b4401ac5eab0f76cf7cec93d; 5.10.267 up to, but not including, 5.11; 5.15.218 up to, but not including, 5.16; and 1 more ranges | 4753cc37b6606ef9a7ec22861d380d45e2707f9a, f77dc8a75859e559f3238a6d906206259227985e, bfc1704d909dc9911a558b1a5833d3d61a43a1f2, e8c276d4dc0e19ee48385f74426aebc855b49aaf, 5.11, 5.16 |
| Linux | Linux Kernel | 6.2 up to, but not including, 6.6.51; 6.7 up to, but not including, 6.10.10; 6.11 | 6.6.51, 6.10.10 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- LocalThe attacker needs local access or must trick a user into running something.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 7.8 | High | CNA |
| CVSS 3.1 | 7.8 | High | NVD |
Official description
In the Linux kernel, the following vulnerability has been resolved: misc: fastrpc: Fix double free of 'buf' in error path smatch warning: drivers/misc/fastrpc.c:1926 fastrpc_req_mmap() error: double free of 'buf' In fastrpc_req_mmap() error path, the fastrpc buffer is freed in fastrpc_req_munmap_impl() if unmap is successful. But in the end, there is an unconditional call to fastrpc_buf_free(). So the above case triggers the double free of fastrpc buf.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Double Free
The product calls free() twice on the same memory address.
How developers prevent this class of flaw
- Choose a language that provides automatic memory management.
- Ensure that each allocation is freed only once. After freeing a chunk, set the pointer to NULL to ensure the pointer cannot be freed again. In complicated error conditions, be sure that clean-up routines respect the state of allocation properly. If the language is object oriented, ensure that object destructors delete each chunk of memory only once.
- Use a static analysis tool to find double free instances.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
Other references
Recent Double Free vulnerabilities
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
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