How severe is CVE-2023-26920?

CVE-2023-26920 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2023-26920 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-26920?

CVE-2023-26920 affects Naturalintelligence Fast Xml Parser. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-26920?

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

When was CVE-2023-26920 published?

CVE-2023-26920 was published on 2023-12-12 and last updated on 2026-06-17.

CVE-2023-26920

CVE-2023-26920 is a medium-severity vulnerability in Naturalintelligence Fast Xml Parser with a CVSS 3.x base score of 6.5. 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-1321.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
EPSS exploit prediction: 1% (63rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-1321
Affected product: Naturalintelligence Fast Xml Parser
Published: 2023-12-12
Last modified: 2026-06-17

Description

fast-xml-parser before 4.1.2 allows __proto__ for Prototype Pollution.

Frequently asked questions

What is CVE-2023-26920?: fast-xml-parser before 4.1.2 allows __proto__ for Prototype Pollution.
How severe is CVE-2023-26920?: CVE-2023-26920 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2023-26920 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-26920?: CVE-2023-26920 affects Naturalintelligence Fast Xml Parser. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-26920?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-26920 published?: CVE-2023-26920 was published on 2023-12-12 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:naturalintelligence:fast_xml_parser:*:*:*:*:*:*:*:*

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