How severe is CVE-2020-26799?

CVE-2020-26799 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-2020-26799 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2020-26799?

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.

Does CVE-2020-26799 have an EU (EUVD) identifier?

Yes. CVE-2020-26799 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2020-19335.

When was CVE-2020-26799 published?

CVE-2020-26799 was published on 2025-07-21 and last updated on 2026-06-17.

CVE-2020-26799

CVE-2020-26799 is a critical-severity vulnerability 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-79.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 1% (41st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2020-19335
Weakness: CWE-79
Published: 2025-07-21
Last modified: 2026-06-17

Description

A reflected cross-site scripting (XSS) vulnerability was discovered in index.php on Luxcal 4.5.2 which allows an unauthenticated attacker to steal other users' data.

Frequently asked questions

What is CVE-2020-26799?: A reflected cross-site scripting (XSS) vulnerability was discovered in index.php on Luxcal 4.5.2 which allows an unauthenticated attacker to steal other users' data.
How severe is CVE-2020-26799?: CVE-2020-26799 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-2020-26799 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2020-26799?: 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.
Does CVE-2020-26799 have an EU (EUVD) identifier?: Yes. CVE-2020-26799 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2020-19335.
When was CVE-2020-26799 published?: CVE-2020-26799 was published on 2025-07-21 and last updated on 2026-06-17.

References

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