Linux Kernel up to 6.8.6 ena_free_tx_bufs use after free

Summaryinfo

A vulnerability identified as problematic has been detected in Linux Kernel up to 5.10.215/5.15.155/6.1.86/6.6.27/6.8.6. This affects the function ena_free_tx_bufs. This manipulation causes use after free. This vulnerability is tracked as CVE-2024-35958. No exploit exists. You should upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic was found in Linux Kernel up to 5.10.215/5.15.155/6.1.86/6.6.27/6.8.6. Affected by this vulnerability is the function ena_free_tx_bufs. The manipulation with an unknown input leads to a use after free vulnerability. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. The impact remains unknown. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: net: ena: Fix incorrect descriptor free behavior ENA has two types of TX queues: - queues which only process TX packets arriving from the network stack - queues which only process TX packets forwarded to it by XDP_REDIRECT or XDP_TX instructions The ena_free_tx_bufs() cycles through all descriptors in a TX queue and unmaps + frees every descriptor that hasn't been acknowledged yet by the device (uncompleted TX transactions). The function assumes that the processed TX queue is necessarily from the first category listed above and ends up using napi_consume_skb() for descriptors belonging to an XDP specific queue. This patch solves a bug in which, in case of a VF reset, the descriptors aren't freed correctly, leading to crashes.

It is possible to read the advisory at git.kernel.org. This vulnerability is known as CVE-2024-35958 since 05/17/2024. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 12/17/2025).

The vulnerability scanner Nessus provides a plugin with the ID 209785 (EulerOS Virtualization 2.12.0 : kernel (EulerOS-SA-2024-2781)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.10.216, 5.15.156, 6.1.87, 6.6.28 or 6.8.7 eliminates this vulnerability. Applying the patch b26aa765f743/fdfbf54d128a/19ff8fed3338/5c7f2240d983/c31baa07f013/bf02d9fe0063 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at Tenable (209785). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 5.10.215
• 5.15.155
• 6.1.0
• 6.1.1
• 6.1.2
• 6.1.3
• 6.1.4
• 6.1.5
• 6.1.6
• 6.1.7
• 6.1.8
• 6.1.9
• 6.1.10
• 6.1.11
• 6.1.12
• 6.1.13
• 6.1.14
• 6.1.15
• 6.1.16
• 6.1.17
• 6.1.18
• 6.1.19
• 6.1.20
• 6.1.21
• 6.1.22
• 6.1.23
• 6.1.24
• 6.1.25
• 6.1.26
• 6.1.27
• 6.1.28
• 6.1.29
• 6.1.30
• 6.1.31
• 6.1.32
• 6.1.33
• 6.1.34
• 6.1.35
• 6.1.36
• 6.1.37
• 6.1.38
• 6.1.39
• 6.1.40
• 6.1.41
• 6.1.42
• 6.1.43
• 6.1.44
• 6.1.45
• 6.1.46
• 6.1.47
• 6.1.48
• 6.1.49
• 6.1.50
• 6.1.51
• 6.1.52
• 6.1.53
• 6.1.54
• 6.1.55
• 6.1.56
• 6.1.57
• 6.1.58
• 6.1.59
• 6.1.60
• 6.1.61
• 6.1.62
• 6.1.63
• 6.1.64
• 6.1.65
• 6.1.66
• 6.1.67
• 6.1.68
• 6.1.69
• 6.1.70
• 6.1.71
• 6.1.72
• 6.1.73
• 6.1.74
• 6.1.75
• 6.1.76
• 6.1.77
• 6.1.78
• 6.1.79
• 6.1.80
• 6.1.81
• 6.1.82
• 6.1.83
• 6.1.84
• 6.1.85
• 6.1.86
• 6.6.0
• 6.6.1
• 6.6.2
• 6.6.3
• 6.6.4
• 6.6.5
• 6.6.6
• 6.6.7
• 6.6.8
• 6.6.9
• 6.6.10
• 6.6.11
• 6.6.12
• 6.6.13
• 6.6.14
• 6.6.15
• 6.6.16
• 6.6.17
• 6.6.18
• 6.6.19
• 6.6.20
• 6.6.21
• 6.6.22
• 6.6.23
• 6.6.24
• 6.6.25
• 6.6.26
• 6.6.27
• 6.8.0
• 6.8.1
• 6.8.2
• 6.8.3
• 6.8.4
• 6.8.5
• 6.8.6

License

• open-source

Website

• Vendor: https://www.kernel.org/

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Entryinfo

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