Linux Kernel up to 6.12.103/6.18.44/7.1.8 ring-buffer ring_buffer_subbuf_order_set use after free

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.
CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
9.5$5k-$25k0.00

Summaryinfo

A vulnerability described as very critical has been identified in Linux Kernel up to 6.12.103/6.18.44/7.1.8. This issue affects the function ring_buffer_subbuf_order_set of the component ring-buffer. Executing a manipulation can lead to use after free. This vulnerability is registered as CVE-2026-74634. It is possible to launch the attack remotely. No exploit is available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability has been found in Linux Kernel up to 6.12.103/6.18.44/7.1.8 and classified as very critical. This vulnerability affects the function ring_buffer_subbuf_order_set of the component ring-buffer. The manipulation with an unknown input leads to a use after free vulnerability. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: ring-buffer: Prevent subbuf order change when resizing is disabled Because ring_buffer_subbuf_order_set() frees buffer pages, we can't allow it when resizing is disabled. A non-consuming reader is at risk of use-after-free (rb_advance_iter()). Return -EBUSY on resize_disabled, matching ring_buffer_resize() behaviour.

The advisory is shared for download at git.kernel.org. This vulnerability was named CVE-2026-74634 since 08/15/2026. The exploitation appears to be easy. The attack can be initiated remotely. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $5k-$25k (estimation calculated on 09/07/2026).

The vulnerability scanner Nessus provides a plugin with the ID 343049 (Oracle Linux 10 / 9 : Unbreakable Enterprise kernel (ELSA-2026-500248)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.12.104, 6.18.45 or 7.1.9 eliminates this vulnerability. Applying the patch b45b91db41379ee5fb36c187d6d7c37b725cbe8e/62978cf6347972c04130e4e841ba404504d92b32/7568e9e717e7540bd05bcc007f5d76fcaff3cdff/bf98d7b0d5a99991e47e66cee4eb1d3fa514be97 is able to eliminate this problem. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (343049) and CERT Bund (WID-SEC-2026-2970). Once again VulDB remains the best source for vulnerability data.

Affected

  • Open Source Linux Kernel

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 9.9
VulDB Meta Temp Score: 9.5

VulDB Base Score: 9.9
VulDB Temp Score: 9.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
💳💳💳💳💳💳
💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock

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

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

0-DayUnlockUnlockUnlockUnlock
TodayUnlockUnlockUnlockUnlock

Nessus ID: 343049
Nessus Name: Oracle Linux 10 / 9 : Unbreakable Enterprise kernel (ELSA-2026-500248)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.12.104/6.18.45/7.1.9
Patch: b45b91db41379ee5fb36c187d6d7c37b725cbe8e/62978cf6347972c04130e4e841ba404504d92b32/7568e9e717e7540bd05bcc007f5d76fcaff3cdff/bf98d7b0d5a99991e47e66cee4eb1d3fa514be97

Timelineinfo

08/15/2026 CVE reserved
08/22/2026 +7 days Advisory disclosed
08/22/2026 +0 days VulDB entry created
09/07/2026 +16 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-74634 (🔒)
GCVE (CVE): GCVE-0-2026-74634
GCVE (VulDB): GCVE-100-394420
CERT Bund: WID-SEC-2026-2970 - Linux Kernel: Mehrere Schwachstellen ermöglichen nicht spezifizierten Angriff

Entryinfo

Created: 08/22/2026 18:30
Updated: 09/07/2026 04:37
Changes: 08/22/2026 18:30 (59), 08/25/2026 05:44 (7), 09/07/2026 04:37 (2)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

Discussion

No comments yet. Languages: en.

Please log in to comment.

◂ PreviousOverviewNext ▸

Might our Artificial Intelligence support you?

Check our Alexa App!