---
id: CVE-2026-74611
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  tls: rx: restore msg_iter before TLS 1.3 optimistic retry

  tls_decrypt_sg() advances msg->msg_iter when it maps user pages for
  the optimistic TLS 1.3 zero-copy path
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  tls: rx: restore msg_iter before TLS 1.3 optimistic retry

  tls_decrypt_sg() advances msg->msg_iter when it maps user pages for
  the optimistic TLS 1.3 zero-copy path. If…
severity: critical
cvss: 9.8
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'
published: '2026-08-22'
updated: '2026-10-14'
sourceUpdated: '2026-10-14T13:10:00.187'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-74611'
references:
  - url: 'https://git.kernel.org/stable/c/1c8629651cb54f7b51db8fc0b1a9944e4a4b0f5e'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/3c837266a734e2a22b24d2d567404a501d405835'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/68787940274ec89f41dc91b1a68ee1a16a90735f'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/c71bacacd59166adbea423a04e7474b0e8245b84'
  - url: 'https://git.kernel.org/stable/c/3c4e21b1bf8e666a1c141e0f5813ece929570deb'
tags:
  - nvd
  - cve.org
epss: 0.00457
epssPercentile: 0.39484
ingestedAt: '2026-10-14T13:30:58.515Z'
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= ce61327ce989b63c0bd1cc7afee00e218ee696ac <
    68787940274ec89f41dc91b1a68ee1a16a90735f
  - >-
    Linux >= ce61327ce989b63c0bd1cc7afee00e218ee696ac <
    3c837266a734e2a22b24d2d567404a501d405835
  - >-
    Linux >= ce61327ce989b63c0bd1cc7afee00e218ee696ac <
    1c8629651cb54f7b51db8fc0b1a9944e4a4b0f5e
  - Linux 6.0
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: total
  timestamp: '2026-10-16T19:02:18.342764Z'
---

## Overview

In the Linux kernel, the following vulnerability has been resolved:

tls: rx: restore msg_iter before TLS 1.3 optimistic retry

tls_decrypt_sg() advances msg->msg_iter when it maps user pages for
the optimistic TLS 1.3 zero-copy path. If the decrypted record turns
out not to be unpadded application data, tls_decrypt_sw() retries into
a kernel skb, but leaves the iterator advanced.

The subsequent copy from the skb then writes decrypted bytes again at
a later point in the caller iovecs while recvmsg() reports only the
post-retry length. A TLS peer can trigger this after the receiver
enables TLS_RX_EXPECT_NO_PAD.

Revert the iterator by the number of bytes consumed by the optimistic
mapping before retrying without zero-copy.

Add a selftest which sends a TLS 1.3 control record with
TLS_RX_EXPECT_NO_PAD enabled and verifies that recvmsg() does not
overwrite later iovecs beyond the returned length.

## Remediation

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