What is CVE-2026-74742?

CVE-2026-74742 is a High severity Linux kernel vulnerability with a CVSS score of 7.5 out of 10, affecting Linux kernel versions from 6.12.61 onward and patched in 6.12.105, 6.18.46, 7.1.10 and others. CVE-2026-74742 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-74742?

CVE-2026-74742 has a CVSS score of 7.5 out of 10, rated High severity. The vector string is CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Is there a patch available for CVE-2026-74742?

Yes, CVE-2026-74742 has been patched. Fixed versions include 6.12.105, 6.18.46, 7.1.10 and others. If you are running Linux kernel 6.12.61 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-74742 actively exploited?

CVE-2026-74742 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2026-74742

High

In the Linux kernel, the following vulnerability has been resolved: veth: fix queue index used to wake the peer txq in veth_poll veth_poll() derives the index of the peer TX queue to wake from rq->xdp_rxq.queue_index. That field is only initialized by xdp_rxq_info_reg() in veth_enable_xdp_range(), which runs only when an XDP program is attached. On the plain GRO/NAPI path (veth_napi_enable_range()) xdp_rxq_info_reg() is never called, so queue_index stays 0 for every queue, as priv->rq is zero-allocated. So in a multi-queue setup with GRO enabled and no XDP program attached, every NAPI instance looks at the peer's TX queue 0. If veth_xmit() stops peer TX queue 1 because the ptr_ring is full (NETDEV_TX_BUSY), nothing ever wakes it again: the poller draining queue 1 wakes queue 0 instead. veth implements no ndo_tx_timeout, so the netdev watchdog does not kick in either, and the queue stays stopped indefinitely. Derive the index from the position of the rq within priv->rq instead, which is correct regardless of whether XDP was ever enabled. Scripts to reproduce the stall are available at https://github.com/netoptimizer/veth-backpressure-performance-testing

Package Linux Kernel

Published 2026-08-26

Last modified 2026-08-27

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

7.5

out of 10

High

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

None

Availability

High

Vector string

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected versions

Linux kernel versions 6.12.61, 6.16 and later are affected. Fixed in 6.12.105, 6.18.46, 7.1.10, 7.2 and their respective stable series.

Affected from

≥ 6.12.61 ≥ 6.16

Fixed in

✓ 6.12.105 6.12.x ✓ 6.18.46 6.18.x ✓ 7.1.10 7.1.x ✓ 7.2

References

4 total

Details

CVE ID CVE-2026-74742

Severity High

CVSS score 7.5 / 10

CVSS version 3.1

Published 2026-08-26

Modified 2026-08-27

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2026-74742?

CVE-2026-74742 is a High severity Linux kernel vulnerability with a CVSS score of 7.5 out of 10 . It affects Linux kernel versions from 6.12.61 onward and has been patched in 6.12.105, 6.18.46, 7.1.10 and others. CVE-2026-74742 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-74742?

CVE-2026-74742 has a CVSS score of 7.5 out of 10, rated High severity (CVSS 3.1). The vector string is CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
Is there a patch available for CVE-2026-74742?

Yes. CVE-2026-74742 has been patched. Fixed versions include 6.12.105, 6.18.46, 7.1.10 and others. If you are running Linux kernel 6.12.61 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-74742 actively exploited?

No. CVE-2026-74742 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.