How severe is CVE-2020-28194?

CVE-2020-28194 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-2020-28194 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (84th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-28194?

CVE-2020-28194 affects Accel-ppp. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-28194?

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-2020-28194 published?

CVE-2020-28194 was published on 2021-02-01 and last updated on 2026-06-17.

CVE-2020-28194

CVE-2020-28194 is a critical-severity vulnerability in Accel-ppp 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-191.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 3% (84th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-191
Affected product: Accel-ppp
Published: 2021-02-01
Last modified: 2026-06-17

Description

Variable underflow exists in accel-ppp radius/packet.c when receiving a RADIUS vendor-specific attribute with length field is less than 2. It has an impact only when the attacker controls the RADIUS server, which can lead to arbitrary code execution.

Frequently asked questions

What is CVE-2020-28194?: Variable underflow exists in accel-ppp radius/packet.c when receiving a RADIUS vendor-specific attribute with length field is less than 2. It has an impact only when the attacker controls the RADIUS server, which can lead to arbitrary code execution.
How severe is CVE-2020-28194?: CVE-2020-28194 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-2020-28194 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (84th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-28194?: CVE-2020-28194 affects Accel-ppp. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-28194?: 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-2020-28194 published?: CVE-2020-28194 was published on 2021-02-01 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:accel-ppp:accel-ppp:*:*:*:*:*:*:*:*

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