Linux Kernel up to 6.12.82/6.18.23/6.19.13 crypto af_alg_get_rsgl buffer overflow

Summaryinfo

A vulnerability, which was classified as critical, was found in Linux Kernel up to 6.12.82/6.18.23/6.19.13. Affected is the function af_alg_get_rsgl of the component crypto. Executing a manipulation can lead to buffer overflow. This vulnerability appears as CVE-2026-31677. There is no available exploit. You should upgrade the affected component.

Detailsinfo

A vulnerability classified as critical was found in Linux Kernel up to 6.12.82/6.18.23/6.19.13. This vulnerability affects the function af_alg_get_rsgl of the component crypto. The manipulation with an unknown input leads to a buffer overflow vulnerability. The CWE definition for the vulnerability is CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: crypto: af_alg - limit RX SG extraction by receive buffer budget Make af_alg_get_rsgl() limit each RX scatterlist extraction to the remaining receive buffer budget. af_alg_get_rsgl() currently uses af_alg_readable() only as a gate before extracting data into the RX scatterlist. Limit each extraction to the remaining af_alg_rcvbuf(sk) budget so that receive-side accounting matches the amount of data attached to the request. If skcipher cannot obtain enough RX space for at least one chunk while more data remains to be processed, reject the recvmsg call instead of rounding the request length down to zero.

The advisory is available at git.kernel.org. This vulnerability was named CVE-2026-31677 since 03/09/2026. The exploitation appears to be easy. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 04/26/2026).

The vulnerability scanner Nessus provides a plugin with the ID 310337 (Linux Distros Unpatched Vulnerability : CVE-2026-31677), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.12.83, 6.18.24 or 6.19.14 eliminates this vulnerability. Applying the patch 9bf3e6ccfdcfe56ae3190d1ae987dacf1cfef4f9/07c6f6ffe29009426f0bd4d3cfbb6308b8ea8453/4a264b2614c73c96666e196bbabe0cead52bdba7/8eceab19eba9dcbfd2a0daec72e1bf48aa100170 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 databases at Tenable (310337) and EUVD (EUVD-2026-25644). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.12.0
• 6.12.1
• 6.12.2
• 6.12.3
• 6.12.4
• 6.12.5
• 6.12.6
• 6.12.7
• 6.12.8
• 6.12.9
• 6.12.10
• 6.12.11
• 6.12.12
• 6.12.13
• 6.12.14
• 6.12.15
• 6.12.16
• 6.12.17
• 6.12.18
• 6.12.19
• 6.12.20
• 6.12.21
• 6.12.22
• 6.12.23
• 6.12.24
• 6.12.25
• 6.12.26
• 6.12.27
• 6.12.28
• 6.12.29
• 6.12.30
• 6.12.31
• 6.12.32
• 6.12.33
• 6.12.34
• 6.12.35
• 6.12.36
• 6.12.37
• 6.12.38
• 6.12.39
• 6.12.40
• 6.12.41
• 6.12.42
• 6.12.43
• 6.12.44
• 6.12.45
• 6.12.46
• 6.12.47
• 6.12.48
• 6.12.49
• 6.12.50
• 6.12.51
• 6.12.52
• 6.12.53
• 6.12.54
• 6.12.55
• 6.12.56
• 6.12.57
• 6.12.58
• 6.12.59
• 6.12.60
• 6.12.61
• 6.12.62
• 6.12.63
• 6.12.64
• 6.12.65
• 6.12.66
• 6.12.67
• 6.12.68
• 6.12.69
• 6.12.70
• 6.12.71
• 6.12.72
• 6.12.73
• 6.12.74
• 6.12.75
• 6.12.76
• 6.12.77
• 6.12.78
• 6.12.79
• 6.12.80
• 6.12.81
• 6.12.82
• 6.18.0
• 6.18.1
• 6.18.2
• 6.18.3
• 6.18.4
• 6.18.5
• 6.18.6
• 6.18.7
• 6.18.8
• 6.18.9
• 6.18.10
• 6.18.11
• 6.18.12
• 6.18.13
• 6.18.14
• 6.18.15
• 6.18.16
• 6.18.17
• 6.18.18
• 6.18.19
• 6.18.20
• 6.18.21
• 6.18.22
• 6.18.23
• 6.19.0
• 6.19.1
• 6.19.2
• 6.19.3
• 6.19.4
• 6.19.5
• 6.19.6
• 6.19.7
• 6.19.8
• 6.19.9
• 6.19.10
• 6.19.11
• 6.19.12
• 6.19.13

License

• open-source

Website

• Vendor: https://www.kernel.org/

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Entryinfo

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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