Linux: Use After Free
CVE-2022-50328 is a high-severity use after 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 1d4d16daec2a6689b6d3fbfc7d2078643adc6619, d11d2ded293976a1a0d9d9471827a44dc9e3c63f, 2e6d9f381c1ed844531a577783fc352de7a44c8a 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 0.16% 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 1d4d16daec2a6689b6d3fbfc7d2078643adc6619 or d11d2ded293976a1a0d9d9471827a44dc9e3c63f or 2e6d9f381c1ed844531a577783fc352de7a44c8a or effd9b3c029ecdd853a11933dcf857f5a7ca8c3d, whichever matches your release line, or a later version.
- Update Linux Kernel to 5.10.150 or 5.15.75 or 5.19.17 or 6.0.3, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | ff780b91efe901b8eecd8114785abae5341820ad up to, but not including, 1d4d16daec2a6689b6d3fbfc7d2078643adc6619; ff780b91efe901b8eecd8114785abae5341820ad up to, but not including, d11d2ded293976a1a0d9d9471827a44dc9e3c63f; ff780b91efe901b8eecd8114785abae5341820ad up to, but not including, 2e6d9f381c1ed844531a577783fc352de7a44c8a; ff780b91efe901b8eecd8114785abae5341820ad up to, but not including, effd9b3c029ecdd853a11933dcf857f5a7ca8c3d; ff780b91efe901b8eecd8114785abae5341820ad up to, but not including, 243d1a5d505d0b0460c9af0ad56ed4a56ef0bebd; 5.10 | 1d4d16daec2a6689b6d3fbfc7d2078643adc6619, d11d2ded293976a1a0d9d9471827a44dc9e3c63f, 2e6d9f381c1ed844531a577783fc352de7a44c8a, effd9b3c029ecdd853a11933dcf857f5a7ca8c3d, 243d1a5d505d0b0460c9af0ad56ed4a56ef0bebd |
| Linux | Linux Kernel | before 5.10.150; 5.11 up to, but not including, 5.15.75; 5.16 up to, but not including, 5.19.17; 6.0 up to, but not including, 6.0.3 | 5.10.150, 5.15.75, 5.19.17, 6.0.3 |
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: jbd2: fix potential use-after-free in jbd2_fc_wait_bufs In 'jbd2_fc_wait_bufs' use 'bh' after put buffer head reference count which may lead to use-after-free. So judge buffer if uptodate before put buffer head reference count.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Use After Free
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.
How developers prevent this class of flaw
- Choose a language that provides automatic memory management.
- When freeing pointers, be sure to set them to NULL once they are freed. However, the utilization of multiple or complex data structures may lower the usefulness of this strategy.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
- git.kernel.org/stable/c/1d4d16daec2a6689b6d3fbfc7d2078643adc6619
- git.kernel.org/stable/c/243d1a5d505d0b0460c9af0ad56ed4a56ef0bebd
- git.kernel.org/stable/c/2e6d9f381c1ed844531a577783fc352de7a44c8a
- git.kernel.org/stable/c/d11d2ded293976a1a0d9d9471827a44dc9e3c63f
- git.kernel.org/stable/c/effd9b3c029ecdd853a11933dcf857f5a7ca8c3d
Recent Use After 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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