Linux Kernel up to 7.3-rc4 net-smc smcr_port_err 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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9.5$5k-$25k0.45-

Summaryinfo

A vulnerability was found in Linux Kernel up to 7.3-rc4. It has been declared as very critical. Impacted is the function smcr_port_err of the component net-smc. The manipulation results in use after free. This vulnerability is cataloged as CVE-2026-98559. The attack may be launched remotely. There is no exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability classified as very critical has been found in Linux Kernel up to 7.3-rc4. Affected is the function smcr_port_err of the component net-smc. 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. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: net/smc: fix UAF on lgr list traversal in smcr_port_err() smcr_port_err() traverses smc_lgr_list.list without holding smc_lgr_list.lock, allowing a concurrent smc_lgr_terminate_sched() to free an lgr while it is still being dereferenced. Hold smc_lgr_list.lock across the traversal. Update smc_ib_gid_check() to call smcr_port_err() after releasing the lock.

The advisory is shared for download at git.kernel.org. This vulnerability is traded as CVE-2026-98559 since 09/25/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. 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 10/18/2026).

Upgrading to version 5.15.222, 6.1.189, 6.6.158, 6.12.112, 6.18.55, 7.2.9 or 7.3-rc5 eliminates this vulnerability. Applying the patch 34bcf11cd2528ae00bb6d764d808083c66824277/0edcc4284392b28826b5d37532b366b291e6e0fa/00a59600ae72d24859d0ad1783a78bc921bc2599/3d35f069e1c119992000d51236dbe54da2d4e61e/3d65a2eb4449fc9658fb860dea893025d028d90e/a9b968e42690d784c241a0761c10253271f7df5d/61cb282fe97b3b0ba32ca09417a693162bf4ae3f is able to eliminate this problem. The best possible mitigation is suggested to be upgrading to the latest version.

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Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 10.0
VulDB Meta Temp Score: 9.5

VulDB Base Score: 10.0
VulDB Temp Score: 9.5
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: 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 5.15.222/6.1.189/6.6.158/6.12.112/6.18.55/7.2.9/7.3-rc5
Patch: 34bcf11cd2528ae00bb6d764d808083c66824277/0edcc4284392b28826b5d37532b366b291e6e0fa/00a59600ae72d24859d0ad1783a78bc921bc2599/3d35f069e1c119992000d51236dbe54da2d4e61e/3d65a2eb4449fc9658fb860dea893025d028d90e/a9b968e42690d784c241a0761c10253271f7df5d/61cb282fe97b3b0ba32ca09417a693162bf4ae3f

Timelineinfo

09/25/2026 CVE reserved
10/18/2026 +23 days Advisory disclosed
10/18/2026 +0 days VulDB entry created
10/18/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-98559 (🔒)
GCVE (CVE): GCVE-0-2026-98559
GCVE (VulDB): GCVE-100-422064

Entryinfo

Created: 10/18/2026 20:07
Changes: 10/18/2026 20:07 (59)
Complete: 🔍
Cache ID: 216::103

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