wolfSSL up to 5.9.1 integer underflow

CVSS Meta Temp Score
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CTI Interest Score
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2.1$0-$5k2.41

Summaryinfo

A vulnerability categorized as problematic has been discovered in wolfSSL up to 5.9.1. This affects an unknown function. Executing a manipulation can lead to integer underflow. The identification of this vulnerability is CVE-2026-6678. The attack can only be executed locally. There is no exploit available. A patch should be applied to remediate this issue.

Detailsinfo

A vulnerability was found in wolfSSL up to 5.9.1. It has been declared as problematic. This vulnerability affects an unknown functionality. The manipulation with an unknown input leads to a integer underflow vulnerability. The CWE definition for the vulnerability is CWE-191. The product subtracts one value from another, such that the result is less than the minimum allowable integer value, which produces a value that is not equal to the correct result. As an impact it is known to affect availability. CVE summarizes:

Integer underflow in wc_PKCS7_DecryptOri when handling crafted Other Recipient Info, leading to incorrect length handling during decryption.

The weakness was shared by Dikai Zou. The advisory is available at github.com. This vulnerability was named CVE-2026-6678 since 04/20/2026. The exploitation appears to be difficult. Local access is required to approach this attack. Successful exploitation requires user interaction by the victim. 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.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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: 2.2
VulDB Meta Temp Score: 2.1

VulDB Base Score: 2.2
VulDB Temp Score: 2.1
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: Integer underflow
CWE: CWE-191 / CWE-189
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

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

04/20/2026 CVE reserved
06/25/2026 +66 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: Dikai Zou
Status: Confirmed

CVE: CVE-2026-6678 (🔒)
GCVE (CVE): GCVE-0-2026-6678
GCVE (VulDB): GCVE-100-374074

Entryinfo

Created: 06/26/2026 01:25
Changes: 06/26/2026 01:25 (66)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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