CVE-2020-26139: An issue was discovered in the kernel in NetBSD 7.1
47
This month
MEDIUM 5.3WATCHLISTMITIGATEMITIGATEMITIGATE
CVE-2020-26139 is a medium-severity flaw (CVSS 5.3) affecting netbsd, debian linux, c-100 firmware. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
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.
Why this priority
EPSS top 6%: very likely to be exploited
On your watchlist
No fix is published yet: follow the downgrade or mitigation steps.
Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
Published CVE record published
Updated Record last modified
netbsd netbsd MITIGATE
Affected: 7.1
Fixed in: no fixed release known
Safe to downgrade to: a release before 7.1
Check your OS release
cat /etc/os-release; uname -r
Debian / Ubuntu
sudo apt update && sudo apt full-upgrade
RHEL / Amazon Linux / Fedora
sudo dnf upgrade --refresh
Windows
Install the latest cumulative update from Windows Update
If no patch exists yet
OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.
debian debian linux MITIGATE
Affected: 9.0
Fixed in: no fixed release known
Safe to downgrade to: a release before 9.0
Check your OS release
cat /etc/os-release; uname -r
Debian / Ubuntu
sudo apt update && sudo apt full-upgrade
RHEL / Amazon Linux / Fedora
sudo dnf upgrade --refresh
Windows
Install the latest cumulative update from Windows Update
If no patch exists yet
OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.
arista c-100 firmware MITIGATE
Affected: all versions
Fixed in: no fixed release known
Safe to downgrade to: no unaffected older release
Check your OS release
cat /etc/os-release; uname -r
Debian / Ubuntu
sudo apt update && sudo apt full-upgrade
RHEL / Amazon Linux / Fedora
sudo dnf upgrade --refresh
Windows
Install the latest cumulative update from Windows Update
If no patch exists yet
OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.
arista c-110 firmware MITIGATE
Affected: all versions
Fixed in: no fixed release known
Safe to downgrade to: no unaffected older release
Check your OS release
cat /etc/os-release; uname -r
Debian / Ubuntu
sudo apt update && sudo apt full-upgrade
RHEL / Amazon Linux / Fedora
sudo dnf upgrade --refresh
Windows
Install the latest cumulative update from Windows Update
If no patch exists yet
OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.
arista c-120 firmware MITIGATE
Affected: all versions
Fixed in: no fixed release known
Safe to downgrade to: no unaffected older release
Check your OS release
cat /etc/os-release; uname -r
Debian / Ubuntu
sudo apt update && sudo apt full-upgrade
RHEL / Amazon Linux / Fedora
sudo dnf upgrade --refresh
Windows
Install the latest cumulative update from Windows Update
If no patch exists yet
OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.
arista c-130 firmware MITIGATE
Affected: all versions
Fixed in: no fixed release known
Safe to downgrade to: no unaffected older release
Check your OS release
cat /etc/os-release; uname -r
Debian / Ubuntu
sudo apt update && sudo apt full-upgrade
RHEL / Amazon Linux / Fedora
sudo dnf upgrade --refresh
Windows
Install the latest cumulative update from Windows Update
If no patch exists yet
OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.
Verify at the official sourceNVD · CVE Program · Report a problem with this page Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2020-26139?
netbsd: mitigate or apply the listed mitigation; debian linux: mitigate or apply the listed mitigation; c-100 firmware: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.
Is CVE-2020-26139 being exploited?
CVE-2020-26139 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2020-26139 affect?
CVE-2020-26139 affects netbsd, debian linux, c-100 firmware. Severity is medium (CVSS 5.3). 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 la
How urgent is CVE-2020-26139?
Priority 47/100. EPSS top 6%: very likely to be exploited; On your watchlist
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