CVE-2025-40176: In the Linux kernel, the following vulnerability has been resolved: tls: wait for pending async decryptions i

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CRITICAL 9.8REMOTEWATCHLIST

CVE-2025-40176 is a critical-severity flaw (CVSS 9.8) affecting affected software. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

In the Linux kernel, the following vulnerability has been resolved: tls: wait for pending async decryptions if tls_strp_msg_hold fails Async decryption calls tls_strp_msg_hold to create a clone of the input skb to hold references to the memory it uses. If we fail to allocate that clone, proceeding with async decryption can lead to various issues (UAF on the skb, writing into userspace memory after the recv() call has returned). In this case, w

Why this priority

Critical severity
CISA SSVC: automatable with total technical impact
Remotely exploitable, no login, no user action
On your watchlist

A fixed release or distro patch exists.

Risk facts

CVSS score	9.8 (Critical)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	0.5% (top 58%)
CISA exploited list	No
Published	2025-11-12
Last modified	2026-10-19

Publisher (CNA): kernel.org

Last updated 2026-10-19 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Timeline

2025-11-12 11:15 UTCPublished CVE record published
2026-10-19 21:10 UTCUpdated Record last modified

Exact fixes by distribution

Fedora ELN · openjpeg · FIXED · 2.5.4-5.eln159 · FEDORA-2026-1a5f60f401 · source

sudo dnf upgrade --advisory=FEDORA-2026-1a5f60f401

Fedora 46 · trustedqsl · FIXED · 2.8.7-1.fc46 · FEDORA-2026-6b1bc90ebc · source

sudo dnf upgrade --advisory=FEDORA-2026-6b1bc90ebc

Ubuntu 20.04 · linux · NOT AFFECTED

Ubuntu 22.04 · linux · NOT AFFECTED

Ubuntu 25.10 · linux · FIXED · 6.17.0-14.14

sudo apt update && sudo apt install --only-upgrade linux dpkg --compare-versions "$(dpkg-query -W -f='${Version}' linux)" ge "6.17.0-14.14" && echo PATCHED || echo STILL-VULNERABLE

Ubuntu 24.04 · linux · FIXED · 6.8.0-106.106

sudo apt update && sudo apt install --only-upgrade linux dpkg --compare-versions "$(dpkg-query -W -f='${Version}' linux)" ge "6.8.0-106.106" && echo PATCHED || echo STILL-VULNERABLE

Ubuntu 20.04 · linux-hwe-5.15 · NOT AFFECTED

Debian 12 · linux · FIXED · 6.1.158-1

sudo apt update && sudo apt install --only-upgrade linux dpkg --compare-versions "$(dpkg-query -W -f='${Version}' linux)" ge "6.1.158-1" && echo PATCHED || echo STILL-VULNERABLE

Debian 13 · linux · FIXED · 6.12.57-1

sudo apt update && sudo apt install --only-upgrade linux dpkg --compare-versions "$(dpkg-query -W -f='${Version}' linux)" ge "6.12.57-1" && echo PATCHED || echo STILL-VULNERABLE

RHEL 10 · kernel · FIXED · kernel-6.12.0-124.27.1.el10_1

sudo dnf upgrade --advisory=RHSA-2026:0453 rpm -q kernel

RHEL 10.0 Extended Update Support · kernel · FIXED · kernel-6.12.0-55.54.1.el10_0

sudo dnf upgrade --advisory=RHSA-2026:0747 rpm -q kernel

RHEL 9 · kernel · FIXED · kernel-5.14.0-611.16.1.el9_7

sudo dnf upgrade --advisory=RHSA-2025:23241 rpm -q kernel

RHEL 9.2 Update Services for SAP Solutions · kernel · FIXED · kernel-5.14.0-284.152.1.el9_2

sudo dnf upgrade --advisory=RHSA-2026:0535 rpm -q kernel

RHEL 9.2 Update Services for SAP Solutions · kernel-rt · FIXED · kernel-rt-5.14.0-284.152.1.rt14.437.el9_2

sudo dnf upgrade --advisory=RHSA-2026:0534 rpm -q kernel-rt

Amazon Linux 2023 · see advisory · FIXED · ALAS2023-2025-1316 · source

sudo dnf update --advisory=ALAS2023-2025-1316

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2025-40176?

No fixed release is listed yet. Watch the vendor advisory and apply any mitigation shown on this page.

Is CVE-2025-40176 being exploited?

CVE-2025-40176 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2025-40176 affect?

CVE-2025-40176 affects affected software. Severity is critical (CVSS 9.8). In the Linux kernel, the following vulnerability has been resolved: tls: wait for pending async decryptions if tls_strp_msg_hold fails Async decryption calls tls_strp_msg_hold to create a clone of the input skb to hold references to the m

How urgent is CVE-2025-40176?

Priority 58/100. Critical severity; CISA SSVC: automatable with total technical impact; Remotely exploitable, no login, no user action; On your watchlist

Software pages

Linux kernel vulnerabilities

References

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