wolfSSL up to 5.9.1 Message Size nonce re-use

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.
CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
2.5$0-$5k2.50

Summaryinfo

A vulnerability has been found in wolfSSL up to 5.9.1 and classified as problematic. The impacted element is an unknown function of the component Message Size Handler. The manipulation leads to nonce re-use. This vulnerability is referenced as CVE-2026-55967. The attack can only be performed from a local environment. No exploit is available.

Detailsinfo

A vulnerability was found in wolfSSL up to 5.9.1. It has been rated as problematic. This issue affects an unknown part of the component Message Size Handler. The manipulation with an unknown input leads to a nonce re-use vulnerability. Using CWE to declare the problem leads to CWE-323. Nonces should be used for the present occasion and only once. Impacted is confidentiality. The summary by CVE is:

AES-GCM encryption/decryption with extremely large cumulative single message sizes (>64 GiB) were not properly rejected by the streaming APIs, allowing counter wrap, keystream reuse, and consequent plaintext recovery.

The weakness was published by Nvidia Project Vanessa. The advisory is shared at github.com. The identification of this vulnerability is CVE-2026-55967 since 06/18/2026. The exploitation is known to be difficult. An attack has to be approached locally. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1600.001 for this issue.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Name

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: 2.5
VulDB Meta Temp Score: 2.5

VulDB Base Score: 2.5
VulDB Temp Score: 2.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
💳💳💳💳💳💳
💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock

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

Exploitinginfo

Class: Nonce re-use
CWE: CWE-323
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: No

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

0-DayUnlockUnlockUnlockUnlock
TodayUnlockUnlockUnlockUnlock

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

06/18/2026 CVE reserved
06/25/2026 +7 days Advisory disclosed
06/25/2026 +0 days VulDB entry created
06/25/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Researcher: Nvidia Project Vanessa
Status: Confirmed

CVE: CVE-2026-55967 (🔒)
GCVE (CVE): GCVE-0-2026-55967
GCVE (VulDB): GCVE-100-373985

Entryinfo

Created: 06/25/2026 19:39
Changes: 06/25/2026 19:39 (64)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Discussion

No comments yet. Languages: en.

Please log in to comment.

◂ PreviousOverviewNext ▸

Want to know what is going to be exploited?

We predict KEV entries!