Linux: Use After Free
CVE-2022-48962 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 3501da8eb6d0f5f114a09ec953c54423f6f35885, 196e12671cb629d9f3b77b4d8bec854fc445533a, aceec8ab752428d8e151321479e82cc1a40fee2e 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 0.33% 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 3501da8eb6d0f5f114a09ec953c54423f6f35885 or 196e12671cb629d9f3b77b4d8bec854fc445533a or aceec8ab752428d8e151321479e82cc1a40fee2e or e71a46cc8c9ad75f3bb0e4b361e81f79c0214cca, whichever matches your release line, or a later version.
- Update Linux Kernel to 4.9.336 or 4.14.302 or 4.19.269 or 5.4.227, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | 542ae60af24f02e130e62cb3b7c23163a2350056 up to, but not including, 3501da8eb6d0f5f114a09ec953c54423f6f35885; 542ae60af24f02e130e62cb3b7c23163a2350056 up to, but not including, 196e12671cb629d9f3b77b4d8bec854fc445533a; 542ae60af24f02e130e62cb3b7c23163a2350056 up to, but not including, aceec8ab752428d8e151321479e82cc1a40fee2e; 542ae60af24f02e130e62cb3b7c23163a2350056 up to, but not including, e71a46cc8c9ad75f3bb0e4b361e81f79c0214cca; 542ae60af24f02e130e62cb3b7c23163a2350056 up to, but not including, 296a50aa8b2982117520713edc1375777a9f8506; 542ae60af24f02e130e62cb3b7c23163a2350056 up to, but not including, 6f4798ac9c9e98f41553c4f5e6c832c8860a6942; 542ae60af24f02e130e62cb3b7c23163a2350056 up to, but not including, 8595a2db8eb0ffcbb466eb9f4a7507a5ba06ebb9; 542ae60af24f02e130e62cb3b7c23163a2350056 up to, but not including, 4640177049549de1a43e9bc49265f0cdfce08cfd; and 1 more ranges | 3501da8eb6d0f5f114a09ec953c54423f6f35885, 196e12671cb629d9f3b77b4d8bec854fc445533a, aceec8ab752428d8e151321479e82cc1a40fee2e, e71a46cc8c9ad75f3bb0e4b361e81f79c0214cca, 296a50aa8b2982117520713edc1375777a9f8506, 6f4798ac9c9e98f41553c4f5e6c832c8860a6942 |
| Linux | Linux Kernel | 4.8 up to, but not including, 4.9.336; 4.10 up to, but not including, 4.14.302; 4.15 up to, but not including, 4.19.269; 4.20 up to, but not including, 5.4.227; 5.5 up to, but not including, 5.10.159; 5.11 up to, but not including, 5.15.83; 5.16 up to, but not including, 6.0.13; 6.1 | 4.9.336, 4.14.302, 4.19.269, 5.4.227, 5.10.159, 5.15.83 |
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 | 8.8 | High | CNA |
| CVSS 3.1 | 7.8 | High | NVD |
Official description
In the Linux kernel, the following vulnerability has been resolved: net: hisilicon: Fix potential use-after-free in hisi_femac_rx() The skb is delivered to napi_gro_receive() which may free it, after calling this, dereferencing skb may trigger use-after-free.
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: partial).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
- git.kernel.org/stable/c/196e12671cb629d9f3b77b4d8bec854fc445533a
- git.kernel.org/stable/c/296a50aa8b2982117520713edc1375777a9f8506
- git.kernel.org/stable/c/3501da8eb6d0f5f114a09ec953c54423f6f35885
- git.kernel.org/stable/c/4640177049549de1a43e9bc49265f0cdfce08cfd
- git.kernel.org/stable/c/6f4798ac9c9e98f41553c4f5e6c832c8860a6942
- git.kernel.org/stable/c/8595a2db8eb0ffcbb466eb9f4a7507a5ba06ebb9
- git.kernel.org/stable/c/aceec8ab752428d8e151321479e82cc1a40fee2e
- git.kernel.org/stable/c/e71a46cc8c9ad75f3bb0e4b361e81f79c0214cca
Recent Use After Free vulnerabilities
- 7.0 High severity
- 7.0 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
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