How severe is CVE-2026-40544?

CVE-2026-40544 has a CVSS 4.0 base score of 5.1, rated medium severity.

Is CVE-2026-40544 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (21st percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-40544?

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

Does CVE-2026-40544 have an EU (EUVD) identifier?

Yes. CVE-2026-40544 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-33610.

When was CVE-2026-40544 published?

CVE-2026-40544 was published on 2026-06-01 and last updated on 2026-06-17.

CVE-2026-40544

CVE-2026-40544 is a medium-severity vulnerability with a CVSS 4.0 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-79.

Key facts

Severity: Medium (CVSS 4.0 base score 5.1)
EPSS exploit prediction: 0% (21st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-33610
Weakness: CWE-79
Published: 2026-06-01
Last modified: 2026-06-17

Description

SOPlanning is vulnerable to Stored Cross-Site Scripting (XSS) via /process/upload_backup endpoint. An authenticated attacker with access to the backup functionality can upload a crafted ZIP archive containing a malicious user.csv file with embedded JavaScript. The injected code is executed in the victim’s browser when a user clicks the Edit button for the malicious backup. This issue affects SOPlanning version 1.55 and below.

Frequently asked questions

What is CVE-2026-40544?: SOPlanning is vulnerable to Stored Cross-Site Scripting (XSS) via /process/upload_backup endpoint. An authenticated attacker with access to the backup functionality can upload a crafted ZIP archive containing a malicious user.csv file with embedded JavaScript. The injected code is executed in the victim’s browser when a user clicks the Edit button for the malicious backup. This issue affects SOPlanning version 1.55 and below.
How severe is CVE-2026-40544?: CVE-2026-40544 has a CVSS 4.0 base score of 5.1, rated medium severity.
Is CVE-2026-40544 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (21st percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-40544?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-40544 have an EU (EUVD) identifier?: Yes. CVE-2026-40544 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-33610.
When was CVE-2026-40544 published?: CVE-2026-40544 was published on 2026-06-01 and last updated on 2026-06-17.

References

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CVE-2022-4361 — Critical (CVSS 10.0): Keycloak, an open-source identity and access management solution, has a cross-site scripting (XSS) vulnerability in the…

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