How severe is CVE-2021-27372?

CVE-2021-27372 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-27372 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-27372?

CVE-2021-27372 affects Realtek Xpon Rtl9601d Software Development Kit. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-27372?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2021-27372 published?

CVE-2021-27372 was published on 2021-03-25 and last updated on 2026-06-17.

CVE-2021-27372

CVE-2021-27372 is a critical-severity vulnerability in Realtek Xpon Rtl9601d Software Development Kit with a CVSS 3.x base score of 9.8. 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-522.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 10.0
EPSS exploit prediction: 2% (73rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-522
Affected product: Realtek Xpon Rtl9601d Software Development Kit
Published: 2021-03-25
Last modified: 2026-06-17

Description

Realtek xPON RTL9601D SDK 1.9 stores passwords in plaintext which may allow attackers to possibly gain access to the device with root permissions via the build-in network monitoring tool and execute arbitrary commands.

Frequently asked questions

What is CVE-2021-27372?: Realtek xPON RTL9601D SDK 1.9 stores passwords in plaintext which may allow attackers to possibly gain access to the device with root permissions via the build-in network monitoring tool and execute arbitrary commands.
How severe is CVE-2021-27372?: CVE-2021-27372 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-27372 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-27372?: CVE-2021-27372 affects Realtek Xpon Rtl9601d Software Development Kit. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-27372?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-27372 published?: CVE-2021-27372 was published on 2021-03-25 and last updated on 2026-06-17.

References

https://www.realtek.com/images/safe-report/RTL9601D_CVE-2021-27372.pdf

Affected products (1)

cpe:2.3:a:realtek:xpon_rtl9601d_software_development_kit:1.9:*:*:*:*:*:*:*

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