Skip to main content

Hostapd CVE-2021-30004

MEDIUM
Improper Input Validation (CWE-20)
2021-04-02 cve@mitre.org
5.3
CVSS 3.1 · NVD
View

Vulnerability Assessment

Weakness
CWE
OWASP Top 10:2025
A05:2025 - Injection
ASVS 5.0
V2 - Validation and Business Logic Input validation, allowlisting
Impact

CVSS score of 5.3 (MEDIUM). Attack characteristics: network attack vector, low complexity, no privileges required, no user interaction not required. EPSS exploitation probability: 1.67%.

Exploit ScenarioDerived

This vulnerability can be exploited remotely over the network. Successful exploitation could compromise the medium-severity affected system.

This Month Plan within 30 days. Why: MEDIUM severity (CVSS 4.0-6.9).
Patch available 1.7% exploitation probability (EPSS)

Get an e-mail when this CVE is exploited, patched or re-scored. Free account.

Alert me

AnalysisAI

In wpa_supplicant and hostapd 2.9, forging attacks may occur because AlgorithmIdentifier parameters are mishandled in tls/pkcs1.c and tls/x509v3.c. Rated medium severity (CVSS 5.3), this vulnerability is remotely exploitable, no authentication required, low attack complexity.

RemediationAI

A vendor patch is available. Apply the latest security update as soon as possible. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.

Affects your stack

Find out whether the stacks and servers you run are on an affected version.

Checking this CVE against your own stacks and servers is part of the Basic plan and up.

Technical ContextAI · show details

This vulnerability is classified under CWE-20. In wpa_supplicant and hostapd 2.9, forging attacks may occur because AlgorithmIdentifier parameters are mishandled in tls/pkcs1.c and tls/x509v3.c. Affected products include: W1.Fi Hostapd, W1.Fi Wpa Supplicant.

Know when Hostapd gets its next vulnerability

  • Watch products and get an email when something new is published
  • Check this CVE against your own stack and servers
  • Exploit and PoC references, threat intelligence from 22 sources

No credit card · 7-day full trial

Severity by source

NVD PRIMARY 5.3 MEDIUM
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
Low
Availability
None

DescriptionNVD

In wpa_supplicant and hostapd 2.9, forging attacks may occur because AlgorithmIdentifier parameters are mishandled in tls/pkcs1.c and tls/x509v3.c.

Threat Intelligence Overview

EPSS Score
1.7%
Top 26% exploitable
Data Quality
4 sources
Confidence: Medium

How this decision was reached

The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.

SignalValue
Severity MEDIUM
CISA KEV No
Public POC No
EPSS 1.7%
Patch available Yes
Active threat No
Deciding rule
MEDIUM severity (CVSS 4.0-6.9)
What every action level means
Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.
Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.
This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.
This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.
Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

SSVC AssessmentENISA

SSVC Decision· derived
Scheduled
Exploitation· derived
None
System Exposure· derived
Open
Automatable· derived
Yes
Human Impact· derived
Medium

Priority Score

28
Low Medium High Critical
KEV: 0
EPSS: +2
CVSS: +26
PoC: 0
Weaponized: 0
Threat intel: 0
Gov advisory: 0

Attack Technique

Information disclosure occurs when an application unintentionally exposes sensitive data that aids attackers in reconnaissance or directly compromises security.

Affected Products (CPE)NVD

cpe:2.3:a:w1.fi:hostapd:2.9:*:*:*:*:*:*:*
cpe:2.3:a:w1.fi:wpa_supplicant:2.9:*:*:*:*:*:*:*
CVE-2017-13082 HIGH POC
8.1 Oct 17

Wi-Fi Protected Access (WPA and WPA2) that supports IEEE 802.11r allows reinstallation of the Pairwise Transient Key (PT

CVE-2019-9499 HIGH
8.1 Apr 17

The implementations of EAP-PWD in wpa_supplicant EAP Peer, when built against a crypto library missing explicit validati

CVE-2019-9498 HIGH
8.1 Apr 17

The implementations of EAP-PWD in hostapd EAP Server, when built against a crypto library missing explicit validation on

CVE-2019-9497 HIGH
8.1 Apr 17

The implementations of EAP-PWD in hostapd EAP Server and wpa_supplicant EAP Peer do not validate the scalar and element

CVE-2014-3686 MEDIUM
6.8 Oct 16

wpa_supplicant and hostapd 0.7.2 through 2.2, when running with certain configurations and using wpa_cli or hostapd_cli

CVE-2016-4476 HIGH
7.5 May 09

hostapd 0.6.7 through 2.5 and wpa_supplicant 0.6.7 through 2.5 do not reject \n and \r characters in passphrase paramete

CVE-2020-12695 HIGH
7.5 Jun 08

The Open Connectivity Foundation UPnP specification before 2020-04-17 does not forbid the acceptance of a subscription r

CVE-2019-9496 HIGH
7.5 Apr 17

An invalid authentication sequence could result in the hostapd process terminating due to missing state validation steps

CVE-2026-58374 HIGH
7.1 Jun 30

Denial of service in hostapd 2.11 through pre-2.12 development snapshots (built with CONFIG_IEEE80211BE) lets an unauthe

CVE-2017-13084 MEDIUM
6.8 Oct 17

Wi-Fi Protected Access (WPA and WPA2) allows reinstallation of the Station-To-Station-Link (STSL) Transient Key (STK) du

CVE-2017-13077 MEDIUM
6.8 Oct 17

Wi-Fi Protected Access (WPA and WPA2) allows reinstallation of the Pairwise Transient Key (PTK) Temporal Key (TK) during

CVE-2017-13086 MEDIUM
6.8 Oct 17

Wi-Fi Protected Access (WPA and WPA2) allows reinstallation of the Tunneled Direct-Link Setup (TDLS) Peer Key (TPK) duri

This site uses cookies essential for authentication and security. No tracking or analytics cookies are used. Privacy Policy