Medium severity6.5NVD Advisory· Published Nov 21, 2025· Updated Jun 17, 2026

CVE-2025-11933

Description

Improper Input Validation in the TLS 1.3 CKS extension parsing in wolfSSL 5.8.2 and earlier on multiple platforms allows a remote unauthenticated attacker to potentially cause a denial-of-service via a crafted ClientHello message with duplicate CKS extensions.

AI Insight

LLM-synthesized narrative grounded in this CVE's description and references.

Affected products

WolfSSL/Wolfssl2 versions
cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:*+ 1 more
- cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:*range: >=5.8.2,<5.8.4
- (no CPE)range: <=5.8.2
wofSSL/wolfSSLv5
Range: 3.12.0

Patches

Vulnerability mechanics

References

github.com/wolfSSL/wolfssl/pull/9132nvdIssue TrackingPatch

News mentions

No linked articles in our index yet.

Severity

MediumCVSS v3.1

6.5/ 10

CVSS v42.3

CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Attack vector: Network
Complexity: Low
Privileges: Low
User interaction: None
Scope: Unchanged
Confidentiality: None
Integrity: None
Availability: High

Vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected

Source repo: github.com/wolfSSL/wolfssl

EPSS

Probability of exploitation in the next 30 days.

0.42%

VYPR risk score

Composite of severity, exploitation, and reach.

0.42medium

cvss	0.423
epss	0.000
exploit	0.000
kev	0.000
patch	0.000
ransomware	0.000

Weaknesses

CWE-20
Improper Input Validation

CVE ID

CVE-2025-11933

Credits

JL
Jaehun Lee, Pohang University of Science and Technology (POSTECH)
finder
KB
Kyungmin Bae, Pohang University of Science and Technology (POSTECH)
coordinator