wolfSSL up to 5.9.1 TLS 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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5.4$0-$5k0.00

Summaryinfo

A vulnerability classified as critical was found in wolfSSL up to 5.9.1. Impacted is an unknown function of the component TLS Handler. Executing a manipulation can lead to use after free. This vulnerability appears as CVE-2026-7531. The attack may be performed from remote. There is no available exploit. It is best practice to apply a patch to resolve this issue.

Detailsinfo

A vulnerability was found in wolfSSL up to 5.9.1. It has been declared as critical. This vulnerability affects an unknown function of the component TLS Handler. 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:

Use-after-free in PQC hybrid key-share handling. This is an incomplete-fix follow-up to CVE-2026-5460 (released in 5.9.1): a malicious TLS 1.3 server sending a truncated PQC hybrid KeyShare can still trigger the error cleanup path to operate on freed memory.

The weakness was presented by Thai Duong. The advisory is available at github.com. This vulnerability was named CVE-2026-7531 since 04/30/2026. The exploitation appears to be difficult. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. The technical details are unknown and an exploit is not available.

Applying a patch is able to eliminate this problem. The bugfix is ready for download at github.com.

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Productinfo

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Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 5.6
VulDB Meta Temp Score: 5.4

VulDB Base Score: 5.6
VulDB Temp Score: 5.4
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: 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: Patch
Status: 🔍

0-Day Time: 🔒

Patch: github.com

Timelineinfo

04/30/2026 CVE reserved
06/25/2026 +56 days VulDB entry created
06/26/2026 +0 days Advisory disclosed
06/26/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Researcher: Thai Duong
Status: Confirmed

CVE: CVE-2026-7531 (🔒)
GCVE (CVE): GCVE-0-2026-7531
GCVE (VulDB): GCVE-100-374038

Entryinfo

Created: 06/26/2026 01:18
Changes: 06/26/2026 01:18 (67)
Complete: 🔍
Cache ID: 216::103

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