Linux: Out-of-bounds Read
CVE-2023-53376 is a high-severity out-of-bounds read vulnerability in Linux, with a CVSS 3.1 base score of 7.1 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 6a675a6d57d31da43d8da576465c1cd5d5b0bd3d, 8ac713d2e9845e9234bb12ae5903040685d5aff9, 339e61565f81a6534afdc18fd854b2e2628bf5db 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 0.17% 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 6a675a6d57d31da43d8da576465c1cd5d5b0bd3d or 8ac713d2e9845e9234bb12ae5903040685d5aff9 or 339e61565f81a6534afdc18fd854b2e2628bf5db, whichever matches your release line, or a later version.
- Update Linux Kernel to 6.1.18 or 6.2.5, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | 824a156633dfdb0e17979a0d0bb2c757d1bb949c up to, but not including, 6a675a6d57d31da43d8da576465c1cd5d5b0bd3d; 824a156633dfdb0e17979a0d0bb2c757d1bb949c up to, but not including, 8ac713d2e9845e9234bb12ae5903040685d5aff9; 824a156633dfdb0e17979a0d0bb2c757d1bb949c up to, but not including, 339e61565f81a6534afdc18fd854b2e2628bf5db; 5.14 | 6a675a6d57d31da43d8da576465c1cd5d5b0bd3d, 8ac713d2e9845e9234bb12ae5903040685d5aff9, 339e61565f81a6534afdc18fd854b2e2628bf5db |
| Linux | Linux Kernel | 5.14 up to, but not including, 6.1.18; 6.2 up to, but not including, 6.2.5 | 6.1.18, 6.2.5 |
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
- NoneNothing can be modified.
- 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:N/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 7.8 | High | CNA |
| CVSS 3.1 | 7.1 | High | NVD |
| CVSS 3.1 | 7.1 | High | CISA (ADP) |
Official description
In the Linux kernel, the following vulnerability has been resolved: scsi: mpi3mr: Use number of bits to manage bitmap sizes To allocate bitmaps, the mpi3mr driver calculates sizes of bitmaps using byte as unit. However, bitmap helper functions assume that bitmaps are allocated using unsigned long as unit. This gap causes memory access beyond the bitmap sizes and results in "BUG: KASAN: slab-out-of-bounds". The BUG was observed at firmware download to eHBA-9600. Call trace indicated that the out-of-bounds access happened in find_first_zero_bit() called from mpi3mr_send_event_ack() for miroc->evtack_cmds_bitmap. To fix the BUG, do not use bytes to manage bitmap sizes. Instead, use number of bits, and call bitmap helper functions which take number of bits as arguments. For memory allocation, call bitmap_zalloc() instead of kzalloc() and krealloc(). For memory free, call bitmap_free() instead of kfree(). For zero clear, call bitmap_clear() instead of memset(). Remove three fields for bitmap byte sizes in struct scmd_priv which are no longer required. Replace the field dev_handle_bitmap_sz with dev_handle_bitmap_bits to keep number of bits of removepend_bitmap across resize.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Out-of-bounds Read
The product reads data past the end, or before the beginning, of the intended buffer.
How developers prevent this class of flaw
- Use a language that provides appropriate memory abstractions.
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
Recent Out-of-bounds Read vulnerabilities
- 7.1 High severity
- 7.1 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
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