Linux Kernel up to 6.18.43/7.1.7/7.2-rc5 uprobes hprobe_expire null pointer dereference

CVSS Meta Temp Score
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CTI Interest Score
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6.2$0-$5k0.48

Summaryinfo

A vulnerability has been found in Linux Kernel up to 6.18.43/7.1.7/7.2-rc5 and classified as critical. The impacted element is the function hprobe_expire of the component uprobes. Performing a manipulation results in null pointer dereference. This vulnerability is identified as CVE-2026-74477. The attack can be initiated remotely. There is not any exploit available.

Detailsinfo

A vulnerability classified as critical has been found in Linux Kernel up to 6.18.43/7.1.7/7.2-rc5. This affects the function hprobe_expire of the component uprobes. The manipulation with an unknown input leads to a null pointer dereference vulnerability. CWE is classifying the issue as CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. This is going to have an impact on availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: uprobes: Fix NULL pointer dereference in hprobe_expire() Forking a task that has a pending uretprobe can oops the kernel with a NULL pointer dereference in the clone() path: BUG: kernel NULL pointer dereference, address: 0000000000000018 Oops: 0002 [#1] SMP NOPTI RIP: 0010:hprobe_expire CR2: 0000000000000018 Call Trace: uprobe_copy_process copy_process kernel_clone __x64_sys_clone do_syscall_64 entry_SYSCALL_64_after_hwframe This was found on real hosts on Meta fleet. I've got the impression that this is what is happening: CPU 1 CPU 2 (traced task) ----- ------------------- hit uprobe, prepare_uretprobe(): hprobe LEASED, refcount >= 1 uprobe_unregister() put_uprobe(): refcount -> 0 fork() -> dup_utask() hprobe_expire(hprobe, true) try_get_uprobe() -> NULL get_uprobe(NULL) <-- Oops Only take the extra reference when the uprobe is non-NULL; a NULL means it is gone and is the correct value to return.

It is possible to read the advisory at git.kernel.org. This vulnerability is uniquely identified as CVE-2026-74477 since 08/15/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 08/15/2026).

Upgrading to version 6.18.44, 7.1.8 or 7.2-rc6 eliminates this vulnerability. Applying the patch 3bd35a5e272a1b7a3fb43acad9bdc599281b13fa/06c275a6c0a953ef1d763d11a6891fcc69ae2ac0/cc679d7a6303e84d769f2afcde1fc51c51f127cd is able to eliminate this problem.

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Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.5
VulDB Meta Temp Score: 6.2

VulDB Base Score: 6.5
VulDB Temp Score: 6.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Null pointer dereference
CWE: CWE-476 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.18.44/7.1.8/7.2-rc6
Patch: 3bd35a5e272a1b7a3fb43acad9bdc599281b13fa/06c275a6c0a953ef1d763d11a6891fcc69ae2ac0/cc679d7a6303e84d769f2afcde1fc51c51f127cd

Timelineinfo

08/15/2026 Advisory disclosed
08/15/2026 +0 days CVE reserved
08/15/2026 +0 days VulDB entry created
08/15/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-74477 (🔒)
GCVE (CVE): GCVE-0-2026-74477
GCVE (VulDB): GCVE-100-390771

Entryinfo

Created: 08/15/2026 14:55
Changes: 08/15/2026 14:55 (59)
Complete: 🔍
Cache ID: 216::103

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