How severe is CVE-2021-30004?

CVE-2021-30004 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2021-30004 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (74th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-30004?

CVE-2021-30004 primarily affects W1.fi Hostapd. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-30004?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-30004 published?

CVE-2021-30004 was published on 2021-04-02 and last updated on 2026-07-07.

CVE-2021-30004

CVE-2021-30004 is a medium-severity vulnerability in W1.fi Hostapd with a CVSS 3.x base score of 5.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 5.0
EPSS exploit prediction: 2% (74th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: W1.fi Hostapd
Published: 2021-04-02
Last modified: 2026-07-07

Description

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

Frequently asked questions

What is CVE-2021-30004?: In wpa_supplicant and hostapd 2.9, forging attacks may occur because AlgorithmIdentifier parameters are mishandled in tls/pkcs1.c and tls/x509v3.c.
How severe is CVE-2021-30004?: CVE-2021-30004 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2021-30004 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (74th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-30004?: CVE-2021-30004 primarily affects W1.fi Hostapd. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-30004?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-30004 published?: CVE-2021-30004 was published on 2021-04-02 and last updated on 2026-07-07.

References

Affected products (2)

cpe:2.3:a:w1.fi:hostapd:2.9:*:*:*:*:*:*:*
cpe:2.3:a:w1.fi:wpa_supplicant:2.9:*:*:*:*:*:*:*

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