How severe is CVE-2021-40840?

CVE-2021-40840 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2021-40840 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (38th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-40840?

CVE-2021-40840 affects Liveconfig. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-40840?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-40840 published?

CVE-2021-40840 was published on 2022-02-18 and last updated on 2026-06-17.

CVE-2021-40840

CVE-2021-40840 is a medium-severity vulnerability in Liveconfig with a CVSS 3.x base score of 5.4. 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-79.

Key facts

Severity: Medium (CVSS 3.x base score 5.4)
CVSS v2: 3.5
EPSS exploit prediction: 0% (38th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Liveconfig
Published: 2022-02-18
Last modified: 2026-06-17

Description

A Stored XSS issue exists in the admin/users user administration form in LiveConfig 2.12.2.

Frequently asked questions

What is CVE-2021-40840?: A Stored XSS issue exists in the admin/users user administration form in LiveConfig 2.12.2.
How severe is CVE-2021-40840?: CVE-2021-40840 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2021-40840 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (38th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-40840?: CVE-2021-40840 affects Liveconfig. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-40840?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-40840 published?: CVE-2021-40840 was published on 2022-02-18 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:liveconfig:liveconfig:2.12.2:*:*:*:*:*:*:*

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