wolfSSL up to 5.9.1 SNI/ALPN improper authentication

CVSS Meta Temp Score
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CTI Interest Score
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5.1$0-$5k0.00

Summaryinfo

A vulnerability classified as critical was found in wolfSSL up to 5.9.1. This vulnerability affects unknown code of the component SNI/ALPN. Executing a manipulation can lead to improper authentication. This vulnerability is registered as CVE-2026-11703. It is possible to launch the attack remotely. No exploit is available. Applying a patch is advised to resolve this issue.

Detailsinfo

A vulnerability has been found in wolfSSL up to 5.9.1 and classified as critical. This vulnerability affects an unknown function of the component SNI/ALPN. The manipulation with an unknown input leads to a improper authentication vulnerability. The CWE definition for the vulnerability is CWE-287. When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. As an impact it is known to affect integrity. CVE summarizes:

Missing SNI/ALPN binding on stateful (session-ID) resumption, which previously skipped the binding check performed for ticket-based resumption. A cached session could be resumed under a different SNI/ALPN than originally negotiated and, where client-authentication policy differs across virtual hosts, carry the cached peer-authentication state into a context it was not established for. Resumption now verifies the SNI/ALPN binding for all paths and declines (falling back to a full handshake) on mismatch.

The weakness was published by Dikai Zou. The advisory is shared for download at github.com. This vulnerability was named CVE-2026-11703 since 06/09/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are neither technical details nor an exploit publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 323780 (Linux Distros Unpatched Vulnerability : CVE-2026-11703), which helps to determine the existence of the flaw in a target environment.

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

The vulnerability is also documented in the databases at Tenable (323780) and EUVD (EUVD-2026-39576). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

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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: 5.3
VulDB Meta Temp Score: 5.1

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
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: Improper authentication
CWE: CWE-287
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 323780
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-11703

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔒

Patch: github.com

Timelineinfo

06/09/2026 CVE reserved
06/26/2026 +17 days Advisory disclosed
06/26/2026 +0 days VulDB entry created
07/02/2026 +6 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Researcher: Dikai Zou
Status: Confirmed

CVE: CVE-2026-11703 (🔒)
GCVE (CVE): GCVE-0-2026-11703
GCVE (VulDB): GCVE-100-374080
EUVD: 🔒

Entryinfo

Created: 06/26/2026 07:28
Updated: 07/02/2026 18:14
Changes: 06/26/2026 07:28 (67), 06/26/2026 16:02 (1), 07/02/2026 18:14 (2)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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