CVE-2021-45639: Certain NETGEAR devices are affected by reflected XSS

Q: How do I fix CVE-2021-45639?

cbr40 firmware: upgrade to 2.5.0.10; eax20 firmware: upgrade to 1.0.0.32; eax80 firmware: upgrade to 1.0.1.62. Exact commands for each OS are on this page.

Q: Is CVE-2021-45639 being exploited?

CVE-2021-45639 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2021-45639 affect?

CVE-2021-45639 affects cbr40 firmware, eax20 firmware, eax80 firmware. Severity is medium (CVSS 5.2). Certain NETGEAR devices are affected by reflected XSS. This affects CBR40 before 2.5.0.10, EAX20 before 1.0.0.32, EAX80 before 1.0.1.62, EX6120 before 1.0.0.64, EX6130 before 1.0.0.44, EX7000 before 1.0.1.104, EX7500 before 1.0.0.72, R7000

Q: How urgent is CVE-2021-45639?

Priority 31/100. No elevated risk signals yet.

Routine

MEDIUM 5.2UPGRADEUPGRADEUPGRADE

CVE-2021-45639 is a medium-severity flaw (CVSS 5.2) affecting cbr40 firmware, eax20 firmware, eax80 firmware. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

Certain NETGEAR devices are affected by reflected XSS. This affects CBR40 before 2.5.0.10, EAX20 before 1.0.0.32, EAX80 before 1.0.1.62, EX6120 before 1.0.0.64, EX6130 before 1.0.0.44, EX7000 before 1.0.1.104, EX7500 before 1.0.0.72, R7000 before 1.0.11.110, R7900 before 1.0.4.30, R7960P before 1.4.1.66, R8000 before 1.0.4.62, RAX200 before 1.0.2.102, XR300 before 1.0.3.50, EX3700 before 1.0.0.90, MR60 before 1.0.5.102, R7000P before 1.3.2.126, R

Why this priority

No elevated risk signals yet

A fixed release or distro patch exists.

Risk facts

CVSS score	5.2 (Medium)
Attack vector	Adjacent network
Attack complexity	Low
Privileges needed	None
User interaction	Required
EPSS exploit chance	0.6% (top 50%)
CISA exploited list	No
Weakness	CWE-79
Published	2021-12-26
Last modified	2026-06-17

Publisher (CNA): MITRE · Vendor: netgear

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2021-12-26 01:15 UTCPublished CVE record published
2026-06-17 04:13 UTCUpdated Record last modified

netgear cbr40 firmware UPGRADE

Affected: < 2.5.0.10

Fixed in: 2.5.0.10

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.

netgear eax20 firmware UPGRADE

Affected: < 1.0.0.32

Fixed in: 1.0.0.32

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.

netgear eax80 firmware UPGRADE

Affected: < 1.0.1.62

Fixed in: 1.0.1.62

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.

netgear ex6120 firmware UPGRADE

Affected: < 1.0.0.64

Fixed in: 1.0.0.64

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.

netgear ex6130 firmware UPGRADE

Affected: < 1.0.0.44

Fixed in: 1.0.0.44

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.

netgear ex7000 firmware UPGRADE

Affected: < 1.0.1.104

Fixed in: 1.0.1.104

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 source NVD · 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-2021-45639?

cbr40 firmware: upgrade to 2.5.0.10; eax20 firmware: upgrade to 1.0.0.32; eax80 firmware: upgrade to 1.0.1.62. Exact commands for each OS are on this page.

Is CVE-2021-45639 being exploited?

CVE-2021-45639 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-2021-45639 affect?

CVE-2021-45639 affects cbr40 firmware, eax20 firmware, eax80 firmware. Severity is medium (CVSS 5.2). Certain NETGEAR devices are affected by reflected XSS. This affects CBR40 before 2.5.0.10, EAX20 before 1.0.0.32, EAX80 before 1.0.1.62, EX6120 before 1.0.0.64, EX6130 before 1.0.0.44, EX7000 before 1.0.1.104, EX7500 before 1.0.0.72, R7000

How urgent is CVE-2021-45639?

Priority 31/100. No elevated risk signals yet.

Software pages

Netgear vulnerabilities

Related CVEs

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References

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