FreeBSD Kernel up to p0.x/p6/p10/p15 RACK setsockopt use after free

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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8.4$0-$5k3.01-

Summaryinfo

A vulnerability was found in FreeBSD Kernel up to p0.x/p6/p10/p15. It has been rated as very critical. Affected by this vulnerability is the function setsockopt of the component RACK. Performing a manipulation results in use after free. This vulnerability is identified as CVE-2026-49422. The attack is only possible with local access. There is not any exploit available.

Detailsinfo

A vulnerability classified as very critical has been found in FreeBSD Kernel up to p0.x/p6/p10/p15. This affects the function setsockopt of the component RACK. The manipulation with an unknown input leads to a use after free vulnerability. CWE is classifying the issue as CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

The RACK setsockopt(2) handler drops the connection lock in order to copy option data from userspace, then reacquires the lock. After reacquiring, it verifies that the TCP stack had not been switched away, but did not reload its pointer to the stack's per-connection control block. If userspace switches stacks twice during this window, the check will succeed but the saved pointer will refer to freed memory. The bug may be exploitable by an unprivileged local user to escalate privileges.

It is possible to read the advisory at security.freebsd.org. This vulnerability is uniquely identified as CVE-2026-49422 since 05/29/2026. The exploitability is told to be easy. Attacking locally is a requirement. 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 08/19/2026).

Upgrading to version p1, p7, p11 or p16 eliminates this vulnerability.

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

Productinfo

Type

Vendor

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.8
VulDB Meta Temp Score: 8.4

VulDB Base Score: 8.8
VulDB Temp Score: 8.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

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

Exploitinginfo

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

Physical: Partially
Local: Yes
Remote: No

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

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 p1/p7/p11/p16

Timelineinfo

05/29/2026 CVE reserved
08/19/2026 +82 days Advisory disclosed
08/19/2026 +0 days VulDB entry created
08/19/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: security.freebsd.org
Status: Confirmed

CVE: CVE-2026-49422 (🔒)
GCVE (CVE): GCVE-0-2026-49422
GCVE (VulDB): GCVE-100-392931

Entryinfo

Created: 08/19/2026 07:46
Changes: 08/19/2026 07:46 (56)
Complete: 🔍
Cache ID: 216::103

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

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