Linux Kernel up to 5.10.194/5.15.131/6.1.53/6.5.3 fq_pie_timer privilege escalation

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4.4	$0-$5k	0.00

Summaryinfo

A vulnerability marked as critical has been reported in Linux Kernel up to 5.10.194/5.15.131/6.1.53/6.5.3. The impacted element is the function fq_pie_timer. This manipulation causes an unknown weakness. This vulnerability is tracked as CVE-2023-53727. No exploit exists. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical was found in Linux Kernel up to 5.10.194/5.15.131/6.1.53/6.5.3. The impact remains unknown. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: net/sched: fq_pie: avoid stalls in fq_pie_timer() When setting a high number of flows (limit being 65536), fq_pie_timer() is currently using too much time as syzbot reported. Add logic to yield the cpu every 2048 flows (less than 150 usec on debug kernels). It should also help by not blocking qdisc fast paths for too long. Worst case (65536 flows) would need 31 jiffies for a complete scan. Relevant extract from syzbot report: rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 0-.... } 2663 jiffies s: 873 root: 0x1/. rcu: blocking rcu_node structures (internal RCU debug): Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 5177 Comm: syz-executor273 Not tainted 6.5.0-syzkaller-00453-g727dbda16b83 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023 RIP: 0010:check_kcov_mode kernel/kcov.c:173 [inline] RIP: 0010:write_comp_data+0x21/0x90 kernel/kcov.c:236 Code: 2e 0f 1f 84 00 00 00 00 00 65 8b 05 01 b2 7d 7e 49 89 f1 89 c6 49 89 d2 81 e6 00 01 00 00 49 89 f8 65 48 8b 14 25 80 b9 03 00 00 01 ff 00 74 0e 85 f6 74 59 8b 82 04 16 00 00 85 c0 74 4f 8b RSP: 0018:ffffc90000007bb8 EFLAGS: 00000206 RAX: 0000000000000101 RBX: ffffc9000dc0d140 RCX: ffffffff885893b0 RDX: ffff88807c075940 RSI: 0000000000000100 RDI: 0000000000000001 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffffc9000dc0d178 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 0000555555d54380(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f6b442f6130 CR3: 000000006fe1c000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: pie_calculate_probability+0x480/0x850 net/sched/sch_pie.c:415 fq_pie_timer+0x1da/0x4f0 net/sched/sch_fq_pie.c:387 call_timer_fn+0x1a0/0x580 kernel/time/timer.c:1700

It is possible to read the advisory at git.kernel.org. This vulnerability is known as CVE-2023-53727 since 10/22/2025. The exploitation appears to be difficult. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 276841 (Linux Distros Unpatched Vulnerability : CVE-2023-53727), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.10.195, 5.15.132, 6.1.54 or 6.5.4 eliminates this vulnerability. Applying the patch 94d527c3759d76c29220758362f622954612bea7/973a4c302d7f3804098ff9824d9f56926901f293/f39b49077abec4c9c3a4c2966532004851c51006/e093000e7d13569c9cb07d7500acd5142c3c43cb/8c21ab1bae945686c602c5bfa4e3f3352c2452c5 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (276841) and CERT Bund (WID-SEC-2025-2394). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

• Red Hat Enterprise Linux
• SUSE Linux
• Oracle Linux
• Open Source Linux Kernel
• Dell NetWorker

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 5.10.194
• 5.15.131
• 6.1.0
• 6.1.1
• 6.1.2
• 6.1.3
• 6.1.4
• 6.1.5
• 6.1.6
• 6.1.7
• 6.1.8
• 6.1.9
• 6.1.10
• 6.1.11
• 6.1.12
• 6.1.13
• 6.1.14
• 6.1.15
• 6.1.16
• 6.1.17
• 6.1.18
• 6.1.19
• 6.1.20
• 6.1.21
• 6.1.22
• 6.1.23
• 6.1.24
• 6.1.25
• 6.1.26
• 6.1.27
• 6.1.28
• 6.1.29
• 6.1.30
• 6.1.31
• 6.1.32
• 6.1.33
• 6.1.34
• 6.1.35
• 6.1.36
• 6.1.37
• 6.1.38
• 6.1.39
• 6.1.40
• 6.1.41
• 6.1.42
• 6.1.43
• 6.1.44
• 6.1.45
• 6.1.46
• 6.1.47
• 6.1.48
• 6.1.49
• 6.1.50
• 6.1.51
• 6.1.52
• 6.1.53
• 6.5.0
• 6.5.1
• 6.5.2
• 6.5.3

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

• 🔒
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CPE 2.2info

• 🔒
• 🔒
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CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.6
VulDB Meta Temp Score: 4.4

VulDB Base Score: 4.6
VulDB Temp Score: 4.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Privilege escalation
CWE: Unknown
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Nessus ID: 276841
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2023-53727

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 5.10.195/5.15.132/6.1.54/6.5.4
Patch: 94d527c3759d76c29220758362f622954612bea7/973a4c302d7f3804098ff9824d9f56926901f293/f39b49077abec4c9c3a4c2966532004851c51006/e093000e7d13569c9cb07d7500acd5142c3c43cb/8c21ab1bae945686c602c5bfa4e3f3352c2452c5

Timelineinfo

10/22/2025 Advisory disclosed
10/22/2025 +0 days CVE reserved
10/22/2025 +0 days VulDB entry created
02/28/2026 +129 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2023-53727 (🔒)
GCVE (CVE): GCVE-0-2023-53727
GCVE (VulDB): GCVE-100-329347
CERT Bund: WID-SEC-2025-2394 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 10/22/2025 16:38
Updated: 02/28/2026 13:15
Changes: 10/22/2025 16:38 (57), 11/28/2025 08:47 (2), 01/02/2026 09:35 (7), 02/28/2026 13:15 (1)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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