6.3

CVE-2025-11936: wolfssl Improper Input Validation

CVSS: 6.3v4.0MediumAnalyzed
AliasesUBUNTU-CVE-2025-11936DEBIAN-CVE-2025-11936
Published 21-11-2025Last modified 08-12-2025
Open JSON

Vulnerability summary

CVE-2025-11936 is a medium (CVSS 6.3) Improper Input Validation vulnerability in wolfssl. EPSS estimates a 0.43% chance of exploitation in the next 30 days, higher than 35.5% of scored vulnerabilities.

Overall risk
25/100
0100
Medium · default modelHow is this calculated?
CVSS score
6.3/10
010
Medium · v4.0 (CVE.org)
EPSS score
0.43%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 21-11-2025
    PublishedVulnerability first disclosed.
  2. 08-12-2025
    Last modifiedVulnerability information updated.

Description

Improper input validation in the TLS 1.3 KeyShareEntry parsing in wolfSSL v5.8.2 on multiple platforms allows a remote unauthenticated attacker to cause a denial-of-service by sending a crafted ClientHello message containing duplicate KeyShareEntry values for the same supported group, leading to excessive CPU and memory consumption during ClientHello processing.

CVSS metrics

6 scores · 4 sources · 2 versions

EPSS trend

Probability

0.43%

Chance of exploitation in the next 30 days

Percentile

36%

Versus all other CVEs

30-day change

0.00 pp

From 0.43% on 20-09-2026

20-09-202620-10-2026
EPSS score
0.43%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Debian1 product
  • wolfsslAll versions (No fix recorded)
Ubuntu1 product
  • wolfsslAll versions (No fix recorded)
Wolfssl1 product
  • wolfssl≥ 3.12.0, < 5.8.4 | ≥ 5.8.2, < 5.8.4

3 vendors · 3 products

References

5 links