CVE-2025-39764
published 2025-09-11CVE-2025-39764: In the Linux kernel, the following vulnerability has been resolved: netfilter: ctnetlink: remove refcounting in expectation dumpers Same pattern as previous…
PriorityP418medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.15%
5.0th percentile
In the Linux kernel, the following vulnerability has been resolved:
netfilter: ctnetlink: remove refcounting in expectation dumpers
Same pattern as previous patch: do not keep the expectation object
alive via refcount, only store a cookie value and then use that
as the skip hint for dump resumption.
AFAICS this has the same issue as the one resolved in the conntrack
dumper, when we do
if (!refcount_inc_not_zero(&exp->use))
to increment the refcount, there is a chance that exp == last, which
causes a double-increment of the refcount and subsequent memory leak.
Affected
30 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 6.16.3-1 (forky) | linux 6.16.3-1 (forky) |
| linux | linux | — | — |
| linux | linux | >= cf6994c2b9812a9f02b99e89df411ffc5db9c779 < b05500444b8eb97644efdd180839a04a706be97c | b05500444b8eb97644efdd180839a04a706be97c |
| linux | linux | >= cf6994c2b9812a9f02b99e89df411ffc5db9c779 < bada48ad5b0590e318d0f79636ff62a2ef9f4955 | bada48ad5b0590e318d0f79636ff62a2ef9f4955 |
| linux | linux | >= cf6994c2b9812a9f02b99e89df411ffc5db9c779 < 64b7684042246e3238464c66894e30ba30c7e851 | 64b7684042246e3238464c66894e30ba30c7e851 |
| linux | linux | >= cf6994c2b9812a9f02b99e89df411ffc5db9c779 < 9e5021a906532ca16e2aac69c0607711e1c70b1f | 9e5021a906532ca16e2aac69c0607711e1c70b1f |
| linux | linux | >= cf6994c2b9812a9f02b99e89df411ffc5db9c779 < 078d33c95bf534d37aa04269d1ae6158e20082d5 | 078d33c95bf534d37aa04269d1ae6158e20082d5 |
| linux | linux | >= cf6994c2b9812a9f02b99e89df411ffc5db9c779 < a4d634ded4d3d400f115d84f654f316f249531c9 | a4d634ded4d3d400f115d84f654f316f249531c9 |
| linux | linux | >= cf6994c2b9812a9f02b99e89df411ffc5db9c779 < 1492e3dcb2be3aa46d1963da96aa9593e4e4db5a | 1492e3dcb2be3aa46d1963da96aa9593e4e4db5a |
| linux | linux_kernel | — | — |
| linux | linux_kernel | >= 0 < 6.16.3-1 | 6.16.3-1 |
| linux | linux_kernel | >= 2.6.23 < 6.16.2 | 6.16.2 |
| msrc | azl3_kernel_6.6.104.2-4_on_azure_linux_3.0 | — | — |
| msrc | azl3_kernel_6.6.112.1-2_on_azure_linux_3.0 | — | — |
| msrc | azl3_kernel_6.6.117.1-1_on_azure_linux_3.0 | — | — |
| msrc | azl3_kernel_6.6.119.3-1_on_azure_linux_3.0 | — | — |
| msrc | azl3_kernel_6.6.119.3-3_on_azure_linux_3.0 | — | — |
| msrc | azl3_kernel_6.6.121.1-1_on_azure_linux_3.0 | — | — |
| msrc | azl3_kernel_6.6.126.1-1_on_azure_linux_3.0 | — | — |
| msrc | azl3_kernel_6.6.96.2-2_on_azure_linux_3.0 | — | — |
| msrc | cbl2_kernel_5.15.186.1-1_on_cbl_mariner_2.0 | — | — |
| msrc | cbl2_kernel_5.15.200.1-1_on_cbl_mariner_2.0 | — | — |
| msrc | cbl2_kernel_5.15.202.1-1_on_cbl_mariner_2.0 | — | — |
| ubuntu | linux | — | — |
| ubuntu | linux-gcp | — | — |
CVSS provenance
nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM
vendor_debian5.5MEDIUM
vendor_msrc5.5MEDIUM
vendor_redhat5.5MEDIUM
vendor_ubuntu2.0LOW
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Ubuntu
Linux kernel vulnerabilities
vendor_ubuntu·2026-07-20·CVSS 2.0
CVE-2026-46073 [LOW] Linux kernel vulnerabilities
Title: Linux kernel vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some AMD processors did not properly clear data in
the floating point divider unit during speculative execution. A local
attacker could use this to expose sensitive information. (CVE-2025-54505)
It was discovered that some AMD Zen 2 processors did not properly isolate
shared resources in the operation cache. A local attacker could possibly
use this issue to corrupt instructions executed at a higher privilege
level, resulting in privilege escalation. (CVE-2025-54518)
It was discovered that some AMD Zen 5 processors supporting RDSEED
instruction did not properly handle entropy, potentially resulting in the
consumption of insufficiently random values. A local attacke
Red Hat
kernel: Linux kernel: Denial of Service via double-increment of reference count in netfilter
vendor_redhat·2025-09-11·CVSS 5.5
CVE-2025-39764 [MEDIUM] CWE-911 kernel: Linux kernel: Denial of Service via double-increment of reference count in netfilter
kernel: Linux kernel: Denial of Service via double-increment of reference count in netfilter
In the Linux kernel, the following vulnerability has been resolved:
netfilter: ctnetlink: remove refcounting in expectation dumpers
Same pattern as previous patch: do not keep the expectation object
alive via refcount, only store a cookie value and then use that
as the skip hint for dump resumption.
AFAICS this has the same issue as the one resolved in the conntrack
dumper, when we do
if (!refcount_inc_not_zero(&exp->use))
to increment the refcount, there is a chance that exp == last, which
causes a double-increment of the refcount and subsequent memory leak.
A flaw was found in the Linux kernel, specifically within the netfilter: ctnetlink component. A local user could exploit a vulnerability wh
Microsoft
netfilter: ctnetlink: remove refcounting in expectation dumpers
vendor_msrc·2025-09-09·CVSS 5.5
CVE-2025-39764 [MEDIUM] netfilter: ctnetlink: remove refcounting in expectation dumpers
netfilter: ctnetlink: remove refcounting in expectation dumpers
FAQ: Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability?
One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transparency in this work which is why we began publishing CSAF/VEX in October 2025. See this blog post for more information. If impact to additional products is identified, we will update the CVE to reflect this.
Mariner: Mariner
Linux: Linux
Customer Action Required: Yes
Debian
CVE-2025-39764: linux - In the Linux kernel, the following vulnerability has been resolved: netfilter: ...
vendor_debian·2025·CVSS 5.5
CVE-2025-39764 [MEDIUM] CVE-2025-39764: linux - In the Linux kernel, the following vulnerability has been resolved: netfilter: ...
In the Linux kernel, the following vulnerability has been resolved: netfilter: ctnetlink: remove refcounting in expectation dumpers Same pattern as previous patch: do not keep the expectation object alive via refcount, only store a cookie value and then use that as the skip hint for dump resumption. AFAICS this has the same issue as the one resolved in the conntrack dumper, when we do if (!refcount_inc_not_zero(&exp->use)) to increment the refcount, there is a chance that exp == last, which causes a double-increment of the refcount and subsequent memory leak.
Scope: local
bookworm: open
bullseye: open
forky: resolved (fixed in 6.16.3-1)
sid: resolved (fixed in 6.16.3-1)
trixie: open
GHSA
GHSA-rh5v-2xrc-gj9x: In the Linux kernel, the following vulnerability has been resolved:
netfilter: ctnetlink: remove refcounting in expectation dumpers
Same pattern as
ghsa_unreviewed·2025-09-11
CVE-2025-39764 [MEDIUM] GHSA-rh5v-2xrc-gj9x: In the Linux kernel, the following vulnerability has been resolved:
netfilter: ctnetlink: remove refcounting in expectation dumpers
Same pattern as
In the Linux kernel, the following vulnerability has been resolved:
netfilter: ctnetlink: remove refcounting in expectation dumpers
Same pattern as previous patch: do not keep the expectation object
alive via refcount, only store a cookie value and then use that
as the skip hint for dump resumption.
AFAICS this has the same issue as the one resolved in the conntrack
dumper, when we do
if (!refcount_inc_not_zero(&exp->use))
to increment the refcount, there is a chance that exp == last, which
causes a double-increment of the refcount and subsequent memory leak.
OSV
CVE-2025-39764: In the Linux kernel, the following vulnerability has been resolved: netfilter: ctnetlink: remove refcounting in expectation dumpers Same pattern as pr
osv·2025-09-11·CVSS 5.5
CVE-2025-39764 [MEDIUM] CVE-2025-39764: In the Linux kernel, the following vulnerability has been resolved: netfilter: ctnetlink: remove refcounting in expectation dumpers Same pattern as pr
In the Linux kernel, the following vulnerability has been resolved: netfilter: ctnetlink: remove refcounting in expectation dumpers Same pattern as previous patch: do not keep the expectation object alive via refcount, only store a cookie value and then use that as the skip hint for dump resumption. AFAICS this has the same issue as the one resolved in the conntrack dumper, when we do if (!refcount_inc_not_zero(&exp->use)) to increment the refcount, there is a chance that exp == last, which causes a double-increment of the refcount and subsequent memory leak.
No detection rules found.
No public exploits indexed.
https://git.kernel.org/stable/c/078d33c95bf534d37aa04269d1ae6158e20082d5https://git.kernel.org/stable/c/1492e3dcb2be3aa46d1963da96aa9593e4e4db5ahttps://git.kernel.org/stable/c/64b7684042246e3238464c66894e30ba30c7e851https://git.kernel.org/stable/c/9e5021a906532ca16e2aac69c0607711e1c70b1fhttps://git.kernel.org/stable/c/a4d634ded4d3d400f115d84f654f316f249531c9https://git.kernel.org/stable/c/b05500444b8eb97644efdd180839a04a706be97chttps://git.kernel.org/stable/c/bada48ad5b0590e318d0f79636ff62a2ef9f4955https://cert-portal.siemens.com/productcert/html/ssa-019113.htmlhttps://cert-portal.siemens.com/productcert/html/ssa-082556.html
2025-09-11
Published