---
id: CVE-2026-31677
title: 'crypto: af_alg - limit RX SG extraction by receive buffer budget'
summary: |-
  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.

  a…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= e870456d8e7c8d57c059ea479b5aadbb55ff4c3a <
    7e345de2e69475430af85e09210795d8eb8e719c
  - >-
    Linux >= e870456d8e7c8d57c059ea479b5aadbb55ff4c3a <
    9bf3e6ccfdcfe56ae3190d1ae987dacf1cfef4f9
  - >-
    Linux >= e870456d8e7c8d57c059ea479b5aadbb55ff4c3a <
    07c6f6ffe29009426f0bd4d3cfbb6308b8ea8453
  - >-
    Linux >= e870456d8e7c8d57c059ea479b5aadbb55ff4c3a <
    4a264b2614c73c96666e196bbabe0cead52bdba7
  - >-
    Linux >= e870456d8e7c8d57c059ea479b5aadbb55ff4c3a <
    8eceab19eba9dcbfd2a0daec72e1bf48aa100170
  - Linux 4.14
published: '2026-04-25'
updated: '2026-10-21'
sourceUpdated: '2026-10-21T12:39:40.854Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-31677'
references:
  - url: 'https://git.kernel.org/stable/c/7e345de2e69475430af85e09210795d8eb8e719c'
  - url: 'https://git.kernel.org/stable/c/9bf3e6ccfdcfe56ae3190d1ae987dacf1cfef4f9'
  - url: 'https://git.kernel.org/stable/c/07c6f6ffe29009426f0bd4d3cfbb6308b8ea8453'
  - url: 'https://git.kernel.org/stable/c/4a264b2614c73c96666e196bbabe0cead52bdba7'
  - url: 'https://git.kernel.org/stable/c/8eceab19eba9dcbfd2a0daec72e1bf48aa100170'
tags:
  - cve.org
epss: 0.00114
epssPercentile: 0.01399
ingestedAt: '2026-10-21T12:48:53.660Z'
---

## Overview

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.

## Affected

- `Linux >= e870456d8e7c8d57c059ea479b5aadbb55ff4c3a < 7e345de2e69475430af85e09210795d8eb8e719c`
- `Linux >= e870456d8e7c8d57c059ea479b5aadbb55ff4c3a < 9bf3e6ccfdcfe56ae3190d1ae987dacf1cfef4f9`
- `Linux >= e870456d8e7c8d57c059ea479b5aadbb55ff4c3a < 07c6f6ffe29009426f0bd4d3cfbb6308b8ea8453`
- `Linux >= e870456d8e7c8d57c059ea479b5aadbb55ff4c3a < 4a264b2614c73c96666e196bbabe0cead52bdba7`
- `Linux >= e870456d8e7c8d57c059ea479b5aadbb55ff4c3a < 8eceab19eba9dcbfd2a0daec72e1bf48aa100170`
- `Linux 4.14`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.