No exploitation reportedFix available

CVE-2026-30940

Q: Is CVE-2026-30940 actively exploited?

Active exploitation of CVE-2026-30940 has not been confirmed. Its EPSS score was 1.1% on 2026-10-23, the estimated probability of exploitation in the next 30 days.

Q: What is the CVSS score for CVE-2026-30940?

CVE-2026-30940 has a CVSS v3 base score of 7.2 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H.

No exploitation reported by the sources we read.

Published2026-03-31
Fixed in5.2.3
WeaknessCWE-22 · CWE-73

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

baserCMS is a website development framework. Prior to version 5.2.3, a path traversal vulnerability exists in the theme file management API (/baser/api/admin/bc-theme-file/theme_files/add.json) that allows arbitrary file write. An authenticated administrator can include ../ sequences in the path parameter to create a PHP file in an arbitrary directory outside the theme directory, which may result in remote code execution (RCE). This issue has been patched in version 5.2.3.

Timeline

dates in UTC

2026-03-3101:16CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-10-23 21:37 UTC

Indicators tagged with this CVE, per day0 indicators over 7 days

Block these indicators

Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2026-30940?format=txt
CSV export: https://api.ismalicious.com/edl/cve/CVE-2026-30940?format=csv
TAXII collection of exploited CVEs
The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD · OSV

Basercms

Branch	Affected	Fixed in	Source
5.2	< 5.2.3	5.2.3	NVD · OSV

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Fix

Update Basercms to 5.2.3

Advisories and patches

basercms.netVendor Advisory
github.comRelease Notes
github.comVendor Advisory

Detection

Nuclei template: none so far
Exploit-DB: no entry
Proof-of-concept repositories: none listed

Sources

CISA-ADPSSVC decisionnone2026-04-02
OpenCVESSVC decisionnone—
CNACVSS 3.17.2read 2026-10-23
CNAweakness (CWE)CWE-22, CWE-73read 2026-10-23
NVDweakness (CWE)CWE-22read 2026-10-23
FIRST EPSSEPSS score1.1 %2026-10-23
OSVaffected packages—

Technical details

CVSS v3 Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
Published: 2026-03-31
Last Modified: 2026-06-17
NVD status: Analyzed

Frequently asked questions

What is CVE-2026-30940?

Is CVE-2026-30940 actively exploited?

Active exploitation of CVE-2026-30940 has not been confirmed. Its EPSS score was 1.1% on 2026-10-23, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2026-30940?

CVE-2026-30940 has a CVSS v3 base score of 7.2 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H.

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