How severe is CVE-2020-26139?

CVE-2020-26139 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over an adjacent network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2020-26139 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (93rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-26139?

CVE-2020-26139 primarily affects Netbsd. In total, 166 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-26139?

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

When was CVE-2020-26139 published?

CVE-2020-26139 was published on 2021-05-11 and last updated on 2026-06-17.

CVE-2020-26139

CVE-2020-26139 is a medium-severity vulnerability in Netbsd 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-287.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 2.9
EPSS exploit prediction: 6% (93rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Netbsd
Published: 2021-05-11
Last modified: 2026-06-17

Description

An issue was discovered in the kernel in NetBSD 7.1. An Access Point (AP) forwards EAPOL frames to other clients even though the sender has not yet successfully authenticated to the AP. This might be abused in projected Wi-Fi networks to launch denial-of-service attacks against connected clients and makes it easier to exploit other vulnerabilities in connected clients.

Frequently asked questions

What is CVE-2020-26139?: An issue was discovered in the kernel in NetBSD 7.1. An Access Point (AP) forwards EAPOL frames to other clients even though the sender has not yet successfully authenticated to the AP. This might be abused in projected Wi-Fi networks to launch denial-of-service attacks against connected clients and makes it easier to exploit other vulnerabilities in connected clients.
How severe is CVE-2020-26139?: CVE-2020-26139 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over an adjacent network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2020-26139 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (93rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-26139?: CVE-2020-26139 primarily affects Netbsd. In total, 166 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-26139?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-26139 published?: CVE-2020-26139 was published on 2021-05-11 and last updated on 2026-06-17.

References

Affected products (166)

cpe:2.3:o:netbsd:netbsd:7.1:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
cpe:2.3:o:arista:c-100_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:arista:c-110_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:arista:c-120_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:arista:c-130_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:arista:c-200_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:arista:c-230_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:arista:c-235_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:arista:c-250_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:arista:c-260_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:arista:c-65_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:arista:c-75_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:arista:o-105_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:arista:o-90_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:arista:w-118_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:arista:w-68_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:cisco:1100_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:cisco:1100-4p_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:cisco:1100-8p_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:cisco:1101-4p_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:cisco:1109-2p_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:cisco:1109-4p_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:cisco:aironet_1532_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:cisco:aironet_1542d_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:cisco:aironet_1542i_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:cisco:aironet_1552_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:cisco:aironet_1552h_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:cisco:aironet_1572_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:cisco:aironet_1702_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:cisco:aironet_1800_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:cisco:aironet_1800i_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:cisco:aironet_1810_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:cisco:aironet_1810w_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:cisco:aironet_1815_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:cisco:aironet_1815i_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:cisco:aironet_1832_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:cisco:aironet_1842_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:cisco:aironet_1852_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:cisco:aironet_2702_firmware:-:*:*:*:*:*:*:*

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