CVE-2026-23168
published 2026-02-14CVE-2026-23168: In the Linux kernel, the following vulnerability has been resolved: flex_proportions: make fprop_new_period() hardirq safe Bernd has reported a lockdep splat…
PriorityP419medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.11%
1.7th percentile
In the Linux kernel, the following vulnerability has been resolved:
flex_proportions: make fprop_new_period() hardirq safe
Bernd has reported a lockdep splat from flexible proportions code that is
essentially complaining about the following race:
run_timer_softirq - we are in softirq context
call_timer_fn
writeout_period
fprop_new_period
write_seqcount_begin(&p->sequence);
...
blk_mq_end_request()
blk_update_request()
ext4_end_bio()
folio_end_writeback()
__wb_writeout_add()
__fprop_add_percpu_max()
if (unlikely(max_frac sequence);
- sees odd sequence so loops indefinitely
Note that a deadlock like this is only possible if the bdi has configured
maximum fraction of writeout throughput which is very rare in general but
frequent for example for FUSE bdis. To fix this problem we have to make
sure write section of the sequence counter is irqsafe.
Affected
45 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 6.1.162-1 (bookworm) | linux 6.1.162-1 (bookworm) |
| linux | linux | — | — |
| linux | linux | >= a91befde350375b1ff954635acdde14dc92cd9a8 < 0acc9ba7a1b5ba4d998c5753e709be904e179b75 | 0acc9ba7a1b5ba4d998c5753e709be904e179b75 |
| linux | linux | >= a91befde350375b1ff954635acdde14dc92cd9a8 < 884b2590ffcc7222cbbd6298051f4c243cc36f5d | 884b2590ffcc7222cbbd6298051f4c243cc36f5d |
| linux | linux | >= a91befde350375b1ff954635acdde14dc92cd9a8 < 78ede9ebd679dadf480dce6f7b798e3603f88348 | 78ede9ebd679dadf480dce6f7b798e3603f88348 |
| linux | linux | >= a91befde350375b1ff954635acdde14dc92cd9a8 < b91a84299d72ae0e05551e851e47cd3008bd025b | b91a84299d72ae0e05551e851e47cd3008bd025b |
| linux | linux | >= a91befde350375b1ff954635acdde14dc92cd9a8 < dd9e2f5b38f1fdd49b1ab6d3a85f81c14369eacc | dd9e2f5b38f1fdd49b1ab6d3a85f81c14369eacc |
| linux | linux_kernel | — | — |
| linux | linux_kernel | >= 0 < 6.1.162-1 | 6.1.162-1 |
| linux | linux_kernel | >= 0 < 6.12.69-1 | 6.12.69-1 |
| linux | linux_kernel | >= 0 < 6.18.9-1 | 6.18.9-1 |
| linux | linux_kernel | >= 6.0 < 6.1.162 | 6.1.162 |
| linux | linux_kernel | >= 6.13 < 6.18.9 | 6.18.9 |
| linux | linux_kernel | >= 6.2 < 6.6.123 | 6.6.123 |
| linux | linux_kernel | >= 6.7 < 6.12.69 | 6.12.69 |
| ubuntu | linux | — | — |
| ubuntu | linux-aws | — | — |
| ubuntu | linux-aws-fips | — | — |
| ubuntu | linux-azure | — | — |
| ubuntu | linux-azure-6.17 | — | — |
| ubuntu | linux-azure-6.8 | — | — |
| ubuntu | linux-azure-fde-6.17 | — | — |
| ubuntu | linux-azure-fips | — | — |
| ubuntu | linux-fips | — | — |
| 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_ubuntu7.8HIGH
vendor_debian5.5MEDIUM
vendor_redhat5.5MEDIUM
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Ubuntu
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An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- Foo-over-UDP (FOU);
- ARM64 architecture;
- x86 architecture;
- Block layer subsystem;
- Drivers core;
- Null block device driver;
- Bluetooth drivers;
- Counter interface drivers;
- DMA engine subsystem;
- DPLL subsystem;
- GPIO subsystem;
- GPU drivers;
- I2C subsystem;
- IIO ADC drivers;
- IIO subsystem;
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- IOMMU subsystem;
- IRQ chip drivers;
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Summary: Several security issues were fixed in the Linux kernel.
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- Foo-over-UDP (FOU);
- ARM64 architecture;
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
- Drivers core;
- Null block device driver;
- Bluetooth drivers;
- Counter interface drivers;
- DMA engine subsystem;
- DPLL subsystem;
- GPIO subsystem;
- GPU drivers;
- I2C subsystem;
- IIO ADC drivers;
- IIO subsystem;
- InfiniBand drivers;
- On-Chip Interconnect management framework;
- IOMMU subsystem;
- IRQ chip drivers;
- Modular ISDN driver;
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Summary: Several security issues were fixed in the Linux kernel.
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- Foo-over-UDP (FOU);
- ARM64 architecture;
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
- Drivers core;
- Null block device driver;
- Bluetooth drivers;
- Counter interface drivers;
- DMA engine subsystem;
- DPLL subsystem;
- GPIO subsystem;
- GPU drivers;
- I2C subsystem;
- IIO ADC drivers;
- IIO subsystem;
- InfiniBand drivers;
- On-Chip Interconnect management framework;
- IOMMU subsystem;
- IRQ chip drivers;
- Modular ISDN driver;
- LED subsystem;
- Multiple devices driver;
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Title: Linux kernel (OEM) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- Foo-over-UDP (FOU);
- ARM64 architecture;
- x86 architecture;
- Block layer subsystem;
- Drivers core;
- Null block device driver;
- Bluetooth drivers;
- Counter interface drivers;
- DMA engine subsystem;
- DPLL subsystem;
- GPIO subsystem;
- GPU drivers;
- I2C subsystem;
- IIO ADC drivers;
- IIO subsystem;
- On-Chip Interconnect management framework;
- IOMMU subsystem;
- IRQ chip drivers;
- Modular ISDN driver;
- LED subsystem;
- Multiple devices driver;
- UACCE accelerator framework;
- MMC subsystem;
-
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CVE-2025-71190 Linux kernel vulnerabilities
Title: Linux kernel vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- Foo-over-UDP (FOU);
- ARM64 architecture;
- x86 architecture;
- Block layer subsystem;
- Drivers core;
- Null block device driver;
- Bluetooth drivers;
- Counter interface drivers;
- DMA engine subsystem;
- DPLL subsystem;
- GPIO subsystem;
- GPU drivers;
- I2C subsystem;
- IIO ADC drivers;
- IIO subsystem;
- On-Chip Interconnect management framework;
- IOMMU subsystem;
- IRQ chip drivers;
- Modular ISDN driver;
- LED subsystem;
- Multiple devices driver;
- UACCE accelerator framework;
- MMC subsystem;
- Ether
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It was discovered that the Linux kernel algif_aead module did not properly
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A local attacker could use this to escalate privileges, or possibly escape
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It was discovered that the Linux kernel did not properly handle shared page
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Frag. A logic flaw existed in the XFRM ESP-in-TCP subsystem and in the
RxRPC networking subsystem when processing paged fragments. A local
attacker could use this to escalate privileges, or possibly escape a
container. (CVE-2026-43284, CVE-2026-43500, CVE-2026-45998, CVE-2026-46000)
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It was discovered that the Linux kernel algif_aead module did not properly
handle in-place cryptographic operations. This flaw is known as Copy Fail.
A local attacker could use this to escalate privileges, or possibly escape
a container. (CVE-2026-31431)
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Summary: Several security issues were fixed in the Linux kernel.
It was discovered that the Linux kernel algif_aead module did not properly
handle in-place cryptographic operations. This flaw is known as Copy Fail.
A local attacker could use this to escalate privileges, or possibly escape
a container. (CVE-2026-31431)
It was discovered that the Linux kernel did not properly handle shared page
fragments during socket buffer operations, collectively known as Dirty
Frag. A logic flaw existed in the XFRM ESP-in-TCP subsystem and in the
RxRPC networking subsystem when processing paged fragments. A local
attacker could use this to escalate privileges, or possibly escape a
container. (CVE-2026-43284, CVE-2026-43500, CVE-2026-45998, CVE-2026-4600
Ubuntu
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vendor_ubuntu·2026-05-26·CVSS 7.8
CVE-2026-23168 [HIGH] Linux kernel (Azure) vulnerabilities
Title: Linux kernel (Azure) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that the Linux kernel algif_aead module did not properly
handle in-place cryptographic operations. This flaw is known as Copy Fail.
A local attacker could use this to escalate privileges, or possibly escape
a container. (CVE-2026-31431)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- ARM64 architecture;
- x86 architecture;
- Cryptographic API;
- Compute Acceleration Framework;
- Drivers core;
- Null block device driver;
- Ublk userspace block driver;
- Bluetooth drivers;
- Counter interface drivers;
- DMA engine subsystem;
- DPLL
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vendor_ubuntu·2026-05-25
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Summary: Several security issues were fixed in the Linux kernel.
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- ARM64 architecture;
- x86 architecture;
- Compute Acceleration Framework;
- Drivers core;
- Null block device driver;
- Ublk userspace block driver;
- Bluetooth drivers;
- Counter interface drivers;
- DMA engine subsystem;
- DPLL subsystem;
- GPU drivers;
- HID subsystem;
- Intel Trace Hub HW tracing drivers;
- IIO ADC drivers;
- IIO subsystem;
- On-Chip Interconnect management framework;
- IRQ chip drivers;
- Modular ISDN driver;
- LED subsystem;
- Multiple devices driver;
- UACCE accelerator f
Ubuntu
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vendor_ubuntu·2026-05-25·CVSS 7.8
CVE-2026-23168 [HIGH] Linux kernel (NVIDIA) vulnerabilities
Title: Linux kernel (NVIDIA) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that the Linux kernel algif_aead module did not properly
handle in-place cryptographic operations. This flaw is known as Copy Fail.
A local attacker could use this to escalate privileges, or possibly escape
a container. (CVE-2026-31431)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- ARM64 architecture;
- x86 architecture;
- Cryptographic API;
- Compute Acceleration Framework;
- Drivers core;
- Null block device driver;
- Ublk userspace block driver;
- Bluetooth drivers;
- Counter interface drivers;
- DMA engine subsystem;
- DPLL
Ubuntu
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vendor_ubuntu·2026-05-22
CVE-2026-23168 Linux kernel (FIPS) vulnerabilities
Title: Linux kernel (FIPS) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- ARM64 architecture;
- x86 architecture;
- Compute Acceleration Framework;
- Drivers core;
- Null block device driver;
- Ublk userspace block driver;
- Bluetooth drivers;
- Counter interface drivers;
- DMA engine subsystem;
- DPLL subsystem;
- GPU drivers;
- HID subsystem;
- Intel Trace Hub HW tracing drivers;
- IIO ADC drivers;
- IIO subsystem;
- On-Chip Interconnect management framework;
- IRQ chip drivers;
- Modular ISDN driver;
- LED subsystem;
- Multiple devices driver;
- UACCE accelerator framework
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vendor_ubuntu·2026-05-20·CVSS 7.8
CVE-2025-71268 [HIGH] Linux kernel (NVIDIA) vulnerabilities
Title: Linux kernel (NVIDIA) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that the Linux kernel algif_aead module did not properly
handle in-place cryptographic operations. This flaw is known as Copy Fail.
A local attacker could use this to escalate privileges, or possibly escape
a container. (CVE-2026-31431)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- ARM64 architecture;
- x86 architecture;
- Cryptographic API;
- Compute Acceleration Framework;
- Drivers core;
- Null block device driver;
- Ublk userspace block driver;
- Bluetooth drivers;
- Counter interface drivers;
- DMA engine subsystem;
- DPLL
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vendor_ubuntu·2026-05-19·CVSS 7.8
CVE-2025-71268 [HIGH] Linux kernel vulnerabilities
Title: Linux kernel vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that the Linux kernel algif_aead module did not properly
handle in-place cryptographic operations. This flaw is known as Copy Fail.
A local attacker could use this to escalate privileges, or possibly escape
a container. (CVE-2026-31431)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- ARM64 architecture;
- x86 architecture;
- Cryptographic API;
- Compute Acceleration Framework;
- Drivers core;
- Null block device driver;
- Ublk userspace block driver;
- Bluetooth drivers;
- Counter interface drivers;
- DMA engine subsystem;
- DPLL subsyste
Red Hat
kernel: flex_proportions: make fprop_new_period() hardirq safe
vendor_redhat·2026-02-14·CVSS 5.5
CVE-2026-23168 [MEDIUM] CWE-833 kernel: flex_proportions: make fprop_new_period() hardirq safe
kernel: flex_proportions: make fprop_new_period() hardirq safe
In the Linux kernel, the following vulnerability has been resolved:
flex_proportions: make fprop_new_period() hardirq safe
Bernd has reported a lockdep splat from flexible proportions code that is
essentially complaining about the following race:
run_timer_softirq - we are in softirq context
call_timer_fn
writeout_period
fprop_new_period
write_seqcount_begin(&p->sequence);
...
blk_mq_end_request()
blk_update_request()
ext4_end_bio()
folio_end_writeback()
__wb_writeout_add()
__fprop_add_percpu_max()
if (unlikely(max_frac sequence);
- sees odd sequence so loops indefinitely
Note that a deadlock like this is only possible if the bdi has configured
maximum fraction of writeout throughput which is very rare in general but
frequen
Debian
CVE-2026-23168: linux - In the Linux kernel, the following vulnerability has been resolved: flex_propor...
vendor_debian·2026·CVSS 5.5
CVE-2026-23168 [MEDIUM] CVE-2026-23168: linux - In the Linux kernel, the following vulnerability has been resolved: flex_propor...
In the Linux kernel, the following vulnerability has been resolved: flex_proportions: make fprop_new_period() hardirq safe Bernd has reported a lockdep splat from flexible proportions code that is essentially complaining about the following race: run_timer_softirq - we are in softirq context call_timer_fn writeout_period fprop_new_period write_seqcount_begin(&p->sequence); ... blk_mq_end_request() blk_update_request() ext4_end_bio() folio_end_writeback() __wb_writeout_add() __fprop_add_percpu_max() if (unlikely(max_frac sequence); - sees odd sequence so loops indefinitely Note that a deadlock like this is only possible if the bdi has configured maximum fraction of writeout throughput which is very rare in general but frequent for example for FUSE bdis. To fix this problem we have to make s
VulDB
Linux Kernel up to 6.1.161/6.6.122/6.12.68/6.18.8 flex_proportions fprop_new_period deadlock (Nessus ID 299167 / WID-SEC-2026-0421)
vuldb·2026-04-13·CVSS 5.5
CVE-2026-23168 [MEDIUM] Linux Kernel up to 6.1.161/6.6.122/6.12.68/6.18.8 flex_proportions fprop_new_period deadlock (Nessus ID 299167 / WID-SEC-2026-0421)
A vulnerability categorized as critical has been discovered in Linux Kernel up to 6.1.161/6.6.122/6.12.68/6.18.8. This affects the function fprop_new_period of the component flex_proportions. Such manipulation leads to deadlock.
This vulnerability is documented as CVE-2026-23168. The attack requires being on the local network. There is not any exploit available.
It is advisable to upgrade the affected component.
OSV
CVE-2026-23168: In the Linux kernel, the following vulnerability has been resolved: flex_proportions: make fprop_new_period() hardirq safe Bernd has reported a lockde
osv·2026-02-14·CVSS 5.5
CVE-2026-23168 [MEDIUM] CVE-2026-23168: In the Linux kernel, the following vulnerability has been resolved: flex_proportions: make fprop_new_period() hardirq safe Bernd has reported a lockde
In the Linux kernel, the following vulnerability has been resolved: flex_proportions: make fprop_new_period() hardirq safe Bernd has reported a lockdep splat from flexible proportions code that is essentially complaining about the following race: run_timer_softirq - we are in softirq context call_timer_fn writeout_period fprop_new_period write_seqcount_begin(&p->sequence); ... blk_mq_end_request() blk_update_request() ext4_end_bio() folio_end_writeback() __wb_writeout_add() __fprop_add_percpu_max() if (unlikely(max_frac sequence); - sees odd sequence so loops indefinitely Note that a deadlock like this is only possible if the bdi has configured maximum fraction of writeout throughput which is very rare in general but frequent for example for FUSE bdis. To fix this problem we have to make s
GHSA
GHSA-7xmm-c998-f7c9: In the Linux kernel, the following vulnerability has been resolved:
flex_proportions: make fprop_new_period() hardirq safe
Bernd has reported a lock
ghsa_unreviewed·2026-02-14
CVE-2026-23168 [MEDIUM] GHSA-7xmm-c998-f7c9: In the Linux kernel, the following vulnerability has been resolved:
flex_proportions: make fprop_new_period() hardirq safe
Bernd has reported a lock
In the Linux kernel, the following vulnerability has been resolved:
flex_proportions: make fprop_new_period() hardirq safe
Bernd has reported a lockdep splat from flexible proportions code that is
essentially complaining about the following race:
run_timer_softirq - we are in softirq context
call_timer_fn
writeout_period
fprop_new_period
write_seqcount_begin(&p->sequence);
...
blk_mq_end_request()
blk_update_request()
ext4_end_bio()
folio_end_writeback()
__wb_writeout_add()
__fprop_add_percpu_max()
if (unlikely(max_frac sequence);
- sees odd sequence so loops indefinitely
Note that a deadlock like this is only possible if the bdi has configured
maximum fraction of writeout throughput which is very rare in general but
frequent for example for FUSE bdis. To fix this problem we have to
No detection rules found.
No public exploits indexed.
Wiz
CVE-2026-23168 Impact, Exploitability, and Mitigation Steps | Wiz
blogs_wiz·CVSS 5.5
CVE-2026-23168 [MEDIUM] CVE-2026-23168 Impact, Exploitability, and Mitigation Steps | Wiz
## CVE-2026-23168 :
Linux Kernel vulnerability analysis and mitigation
In the Linux kernel, the following vulnerability has been resolved:
flex_proportions: make fprop_new_period() hardirq safe
Bernd has reported a lockdep splat from flexible proportions code that is
essentially complaining about the following race:
...
blk_mq_end_request()
blk_update_request()
ext4_end_bio()
folio_end_writeback()
__wb_writeout_add()
__fprop_add_percpu_max()
if (unlikely(max_frac sequence);
- sees odd sequence so loops indefinitely
Note that a deadlock like this is only possible if the bdi has configured
maximum fraction of writeout throughput which is very rare in general but
frequent for example for FUSE bdis. To fix this problem we have to make
sure write section of the sequence counter is irqsaf
Bugzilla
CVE-2026-23168 kernel: flex_proportions: make fprop_new_period() hardirq safe
bugzilla·2026-02-14·CVSS 5.5
CVE-2026-23168 [MEDIUM] CVE-2026-23168 kernel: flex_proportions: make fprop_new_period() hardirq safe
CVE-2026-23168 kernel: flex_proportions: make fprop_new_period() hardirq safe
In the Linux kernel, the following vulnerability has been resolved:
flex_proportions: make fprop_new_period() hardirq safe
Bernd has reported a lockdep splat from flexible proportions code that is
essentially complaining about the following race:
run_timer_softirq - we are in softirq context
call_timer_fn
writeout_period
fprop_new_period
write_seqcount_begin(&p->sequence);
...
blk_mq_end_request()
blk_update_request()
ext4_end_bio()
folio_end_writeback()
__wb_writeout_add()
__fprop_add_percpu_max()
if (unlikely(max_frac sequence);
- sees odd sequence so loops indefinitely
Note that a deadlock like this is only possible if the bdi has configured
maximum fraction of writeout throughput which is very rare in
https://git.kernel.org/stable/c/0acc9ba7a1b5ba4d998c5753e709be904e179b75https://git.kernel.org/stable/c/78ede9ebd679dadf480dce6f7b798e3603f88348https://git.kernel.org/stable/c/884b2590ffcc7222cbbd6298051f4c243cc36f5dhttps://git.kernel.org/stable/c/b91a84299d72ae0e05551e851e47cd3008bd025bhttps://git.kernel.org/stable/c/dd9e2f5b38f1fdd49b1ab6d3a85f81c14369eacc
2026-02-14
Published