CVE-2020-3423

CVE-2020-3423 is a medium-severity vulnerability in Cisco Ios Xe with a CVSS 3.x base score of 5.1. 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-119.

Key facts

Description

A vulnerability in the implementation of the Lua interpreter that is integrated in Cisco IOS XE Software could allow an authenticated, local attacker to execute arbitrary code with root privileges on the underlying Linux operating system (OS) of an affected device. The vulnerability is due to insufficient restrictions on Lua function calls within the context of user-supplied Lua scripts. An attacker with valid administrative credentials could exploit this vulnerability by submitting a malicious Lua script. When this file is processed, an exploitable buffer overflow condition could occur. A successful exploit could allow the attacker to execute arbitrary code with root privileges on the underlying Linux OS of the affected device.

Frequently asked questions

What is CVE-2020-3423?
A vulnerability in the implementation of the Lua interpreter that is integrated in Cisco IOS XE Software could allow an authenticated, local attacker to execute arbitrary code with root privileges on the underlying Linux operating system (OS) of an affected device. The vulnerability is due to insufficient restrictions on Lua function calls within the context of user-supplied Lua scripts. An attacker with valid administrative credentials could exploit this vulnerability by submitting a malicious Lua script. When this file is processed, an exploitable buffer overflow condition could occur. A successful exploit could allow the attacker to execute arbitrary code with root privileges on the underlying Linux OS of the affected device.
How severe is CVE-2020-3423?
CVE-2020-3423 has a CVSS 3.x base score of 5.1, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is low, integrity high, and availability none.
Is CVE-2020-3423 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (31st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-3423?
CVE-2020-3423 affects Cisco Ios Xe. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-3423?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-3423 published?
CVE-2020-3423 was published on 2020-09-24 and last updated on 2026-06-17.

References

Affected products (1)

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