How severe is CVE-2026-3998?

CVE-2026-3998 has a CVSS 3.x base score of 6.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2026-3998 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (18th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-3998?

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

Does CVE-2026-3998 have an EU (EUVD) identifier?

Yes. CVE-2026-3998 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-22865.

When was CVE-2026-3998 published?

CVE-2026-3998 was published on 2026-04-15 and last updated on 2026-06-17.

CVE-2026-3998

CVE-2026-3998 is a medium-severity vulnerability with a CVSS 3.x base score of 6.4. 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 6.4)
EPSS exploit prediction: 0% (18th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-22865
Weakness: CWE-79
Published: 2026-04-15
Last modified: 2026-06-17

Description

The WM JqMath plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'style' shortcode attribute of the [jqmath] shortcode in all versions up to and including 1.3. This is due to insufficient input sanitization and output escaping on user-supplied shortcode attributes. The generate_jqMathFormula() function directly concatenates the 'style' attribute value into an HTML style attribute without applying esc_attr() or any other escaping. This makes it possible for authenticated attackers, with Contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

Frequently asked questions

What is CVE-2026-3998?: The WM JqMath plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'style' shortcode attribute of the [jqmath] shortcode in all versions up to and including 1.3. This is due to insufficient input sanitization and output escaping on user-supplied shortcode attributes. The generate_jqMathFormula() function directly concatenates the 'style' attribute value into an HTML style attribute without applying esc_attr() or any other escaping. This makes it possible for authenticated attackers, with Contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.
How severe is CVE-2026-3998?: CVE-2026-3998 has a CVSS 3.x base score of 6.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2026-3998 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (18th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-3998?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-3998 have an EU (EUVD) identifier?: Yes. CVE-2026-3998 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-22865.
When was CVE-2026-3998 published?: CVE-2026-3998 was published on 2026-04-15 and last updated on 2026-06-17.

References

Other CWE-79 (Cross-site Scripting (XSS)) vulnerabilities

CVE-2025-49410 — Critical (CVSS 10.0): Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in Imran Emu TC…
CVE-2024-47875 — Critical (CVSS 10.0): DOMPurify is a DOM-only, super-fast, uber-tolerant XSS sanitizer for HTML, MathML and SVG. DOMpurify was vulnerable to…
CVE-2024-6886 — Critical (CVSS 10.0): Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in Gitea…
CVE-2023-45144 — Critical (CVSS 10.0): com.xwiki.identity-oauth:identity-oauth-ui is a package to aid in building identity and service providers based on…
CVE-2023-45138 — Critical (CVSS 10.0): Change Request is an pplication allowing users to request changes on a wiki without publishing the changes directly.…
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…

Browse all CWE-79 (Cross-site Scripting (XSS)) vulnerabilities →