How severe is CVE-2026-44665?

CVE-2026-44665 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2026-44665 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (11th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-44665?

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

Does CVE-2026-44665 have an EU (EUVD) identifier?

Yes. CVE-2026-44665 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-30053.

When was CVE-2026-44665 published?

CVE-2026-44665 was published on 2026-05-13 and last updated on 2026-06-17.

CVE-2026-44665

CVE-2026-44665 is a medium-severity vulnerability with a CVSS 3.x base score of 6.1. 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-91.

Key facts

Severity: Medium (CVSS 3.x base score 6.1)
EPSS exploit prediction: 0% (11th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-30053
Weakness: CWE-91
Published: 2026-05-13
Last modified: 2026-06-17

Description

fast-xml-builder builds XML from JSON. Prior to 1.1.7, when an input data has quotes in attribute values but process entities is not enabled, it breaks the attribute value into multiple attributes. This gives the room for an attacker to insert unwanted attributes to the XML/HTML. This vulnerability is fixed in 1.1.7.

Frequently asked questions

What is CVE-2026-44665?: fast-xml-builder builds XML from JSON. Prior to 1.1.7, when an input data has quotes in attribute values but process entities is not enabled, it breaks the attribute value into multiple attributes. This gives the room for an attacker to insert unwanted attributes to the XML/HTML. This vulnerability is fixed in 1.1.7.
How severe is CVE-2026-44665?: CVE-2026-44665 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2026-44665 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (11th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-44665?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-44665 have an EU (EUVD) identifier?: Yes. CVE-2026-44665 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-30053.
When was CVE-2026-44665 published?: CVE-2026-44665 was published on 2026-05-13 and last updated on 2026-06-17.

References

https://github.com/NaturalIntelligence/fast-xml-builder/security/advisories/GHSA-5wm8-gmm8-39j9

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