CVE-2026-23436
published 2026-04-03CVE-2026-23436: In the Linux kernel, the following vulnerability has been resolved: net: shaper: protect from late creation of hierarchy We look up a netdev during prep of…
PriorityP420medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.12%
2.2th percentile
In the Linux kernel, the following vulnerability has been resolved:
net: shaper: protect from late creation of hierarchy
We look up a netdev during prep of Netlink ops (pre- callbacks)
and take a ref to it. Then later in the body of the callback
we take its lock or RCU which are the actual protections.
The netdev may get unregistered in between the time we take
the ref and the time we lock it. We may allocate the hierarchy
after flush has already run, which would lead to a leak.
Take the instance lock in pre- already, this saves us from the race
and removes the need for dedicated lock/unlock callbacks completely.
After all, if there's any chance of write happening concurrently
with the flush - we're back to leaking the hierarchy.
We may take the lock for devices which don't support shapers but
we're only dealing with SET operations here, not taking the lock
would be optimizing for an error case.
Affected
16 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 6.19.10-1 (forky) | linux 6.19.10-1 (forky) |
| linux | linux | — | — |
| linux | linux | >= 93954b40f6a4fc43226c01a15b02732f884500f1 < 719f6784f918f9e32f3ff3b197f900e852223f9d | 719f6784f918f9e32f3ff3b197f900e852223f9d |
| linux | linux | >= 93954b40f6a4fc43226c01a15b02732f884500f1 < d22921727023e7852704965e935f4d1fc83a5ec9 | d22921727023e7852704965e935f4d1fc83a5ec9 |
| linux | linux | >= 93954b40f6a4fc43226c01a15b02732f884500f1 < d75ec7e8ba1979a1eb0b9211d94d749cdce849c8 | d75ec7e8ba1979a1eb0b9211d94d749cdce849c8 |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | >= 0 < 6.19.10-1 | 6.19.10-1 |
| linux | linux_kernel | >= 6.13.1 < 6.18.20 | 6.18.20 |
| linux | linux_kernel | >= 6.19 < 6.19.10 | 6.19.10 |
CVSS provenance
nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
vendor_redhat5.5LOW
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OSV
CVE-2026-23436: In the Linux kernel, the following vulnerability has been resolved: net: shaper: protect from late creation of hierarchy We look up a netdev during pr
osv·2026-04-03
CVE-2026-23436 CVE-2026-23436: In the Linux kernel, the following vulnerability has been resolved: net: shaper: protect from late creation of hierarchy We look up a netdev during pr
In the Linux kernel, the following vulnerability has been resolved: net: shaper: protect from late creation of hierarchy We look up a netdev during prep of Netlink ops (pre- callbacks) and take a ref to it. Then later in the body of the callback we take its lock or RCU which are the actual protections. The netdev may get unregistered in between the time we take the ref and the time we lock it. We may allocate the hierarchy after flush has already run, which would lead to a leak. Take the instance lock in pre- already, this saves us from the race and removes the need for dedicated lock/unlock callbacks completely. After all, if there's any chance of write happening concurrently with the flush - we're back to leaking the hierarchy. We may take the lock for devices which don't support shapers
GHSA
GHSA-943r-726h-fc9x: In the Linux kernel, the following vulnerability has been resolved:
net: shaper: protect from late creation of hierarchy
We look up a netdev during
ghsa_unreviewed·2026-04-03
CVE-2026-23436 GHSA-943r-726h-fc9x: In the Linux kernel, the following vulnerability has been resolved:
net: shaper: protect from late creation of hierarchy
We look up a netdev during
In the Linux kernel, the following vulnerability has been resolved:
net: shaper: protect from late creation of hierarchy
We look up a netdev during prep of Netlink ops (pre- callbacks)
and take a ref to it. Then later in the body of the callback
we take its lock or RCU which are the actual protections.
The netdev may get unregistered in between the time we take
the ref and the time we lock it. We may allocate the hierarchy
after flush has already run, which would lead to a leak.
Take the instance lock in pre- already, this saves us from the race
and removes the need for dedicated lock/unlock callbacks completely.
After all, if there's any chance of write happening concurrently
with the flush - we're back to leaking the hierarchy.
We may take the lock for devices which don't support sh
Red Hat
kernel: net: shaper: protect from late creation of hierarchy
vendor_redhat·2026-04-03·CVSS 5.5
CVE-2026-23436 [LOW] CWE-367 kernel: net: shaper: protect from late creation of hierarchy
kernel: net: shaper: protect from late creation of hierarchy
In the Linux kernel, the following vulnerability has been resolved:
net: shaper: protect from late creation of hierarchy
We look up a netdev during prep of Netlink ops (pre- callbacks)
and take a ref to it. Then later in the body of the callback
we take its lock or RCU which are the actual protections.
The netdev may get unregistered in between the time we take
the ref and the time we lock it. We may allocate the hierarchy
after flush has already run, which would lead to a leak.
Take the instance lock in pre- already, this saves us from the race
and removes the need for dedicated lock/unlock callbacks completely.
After all, if there's any chance of write happening concurrently
with the flush - we're back to leaking the hierarchy
Debian
CVE-2026-23436: linux - In the Linux kernel, the following vulnerability has been resolved: net: shaper...
vendor_debian·2026
CVE-2026-23436 [LOW] CVE-2026-23436: linux - In the Linux kernel, the following vulnerability has been resolved: net: shaper...
In the Linux kernel, the following vulnerability has been resolved: net: shaper: protect from late creation of hierarchy We look up a netdev during prep of Netlink ops (pre- callbacks) and take a ref to it. Then later in the body of the callback we take its lock or RCU which are the actual protections. The netdev may get unregistered in between the time we take the ref and the time we lock it. We may allocate the hierarchy after flush has already run, which would lead to a leak. Take the instance lock in pre- already, this saves us from the race and removes the need for dedicated lock/unlock callbacks completely. After all, if there's any chance of write happening concurrently with the flush - we're back to leaking the hierarchy. We may take the lock for devices which don't support shapers
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2026-23436 kernel: net: shaper: protect from late creation of hierarchy
bugzilla·2026-04-03·CVSS 5.5
CVE-2026-23436 [MEDIUM] CVE-2026-23436 kernel: net: shaper: protect from late creation of hierarchy
CVE-2026-23436 kernel: net: shaper: protect from late creation of hierarchy
In the Linux kernel, the following vulnerability has been resolved:
net: shaper: protect from late creation of hierarchy
We look up a netdev during prep of Netlink ops (pre- callbacks)
and take a ref to it. Then later in the body of the callback
we take its lock or RCU which are the actual protections.
The netdev may get unregistered in between the time we take
the ref and the time we lock it. We may allocate the hierarchy
after flush has already run, which would lead to a leak.
Take the instance lock in pre- already, this saves us from the race
and removes the need for dedicated lock/unlock callbacks completely.
After all, if there's any chance of write happening concurrently
with the flush - we're back to le
Wiz
CVE-2026-23436 Impact, Exploitability, and Mitigation Steps | Wiz
blogs_wiz
CVE-2026-23436 CVE-2026-23436 Impact, Exploitability, and Mitigation Steps | Wiz
## CVE-2026-23436 :
Linux Kernel vulnerability analysis and mitigation
In the Linux kernel, the following vulnerability has been resolved:
net: shaper: protect from late creation of hierarchy
We look up a netdev during prep of Netlink ops (pre- callbacks)
and take a ref to it. Then later in the body of the callback
we take its lock or RCU which are the actual protections.
The netdev may get unregistered in between the time we take
the ref and the time we lock it. We may allocate the hierarchy
after flush has already run, which would lead to a leak.
Take the instance lock in pre- already, this saves us from the race
and removes the need for dedicated lock/unlock callbacks completely.
After all, if there's any chance of write happening concurrently
with the flush - we're back to leakin
2026-04-03
Published