Linux: Use After Free
CVE-2024-50274 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 fa4d906ad0fb63a980a1d586a061c78ea1a345ba, 81d2fb4c7c18a3b36ba3e00b9d5b753107472d75 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 0.23% 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 fa4d906ad0fb63a980a1d586a061c78ea1a345ba or 81d2fb4c7c18a3b36ba3e00b9d5b753107472d75, whichever matches your release line, or a later version.
- Update Linux Kernel to 6.11.8 or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | 02cbfba1add5bd9088c7d14c6b93b77a6ea8f3bb up to, but not including, fa4d906ad0fb63a980a1d586a061c78ea1a345ba; 02cbfba1add5bd9088c7d14c6b93b77a6ea8f3bb up to, but not including, 81d2fb4c7c18a3b36ba3e00b9d5b753107472d75; 6.7 | fa4d906ad0fb63a980a1d586a061c78ea1a345ba, 81d2fb4c7c18a3b36ba3e00b9d5b753107472d75 |
| Linux | Linux Kernel | 6.7 up to, but not including, 6.11.8; 6.12 | 6.11.8 |
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 | NVD |
| CVSS 3.1 | 7.8 | High | CISA (ADP) |
Official description
In the Linux kernel, the following vulnerability has been resolved: idpf: avoid vport access in idpf_get_link_ksettings When the device control plane is removed or the platform running device control plane is rebooted, a reset is detected on the driver. On driver reset, it releases the resources and waits for the reset to complete. If the reset fails, it takes the error path and releases the vport lock. At this time if the monitoring tools tries to access link settings, it call traces for accessing released vport pointer. To avoid it, move link_speed_mbps to netdev_priv structure which removes the dependency on vport pointer and the vport lock in idpf_get_link_ksettings. Also use netif_carrier_ok() to check the link status and adjust the offsetof to use link_up instead of link_speed_mbps.
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
Recent Use After Free vulnerabilities
- 7.8 High severity
- 7.8 High severity
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- 7.0 High severity
- 7.8 High severity
- 7.8 High severity
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