How severe is CVE-2021-40894?

CVE-2021-40894 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-40894 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (58th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-40894?

CVE-2021-40894 affects Underscore-99xp Project Underscore-99xp. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-40894?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-40894 published?

CVE-2021-40894 was published on 2022-06-24 and last updated on 2026-06-17.

CVE-2021-40894

CVE-2021-40894 is a high-severity vulnerability in Underscore-99xp Project Underscore-99xp with a CVSS 3.x base score of 7.5. 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-1333.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (58th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-1333
Affected product: Underscore-99xp Project Underscore-99xp
Published: 2022-06-24
Last modified: 2026-06-17

Description

A Regular Expression Denial of Service (ReDOS) vulnerability was discovered in underscore-99xp v1.7.2 when the deepValueSearch function is called.

Frequently asked questions

What is CVE-2021-40894?: A Regular Expression Denial of Service (ReDOS) vulnerability was discovered in underscore-99xp v1.7.2 when the deepValueSearch function is called.
How severe is CVE-2021-40894?: CVE-2021-40894 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-40894 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (58th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-40894?: CVE-2021-40894 affects Underscore-99xp Project Underscore-99xp. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-40894?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-40894 published?: CVE-2021-40894 was published on 2022-06-24 and last updated on 2026-06-17.

References

https://github.com/yetingli/SaveResults/blob/main/js/underscore-99xp.mjs

Affected products (1)

cpe:2.3:a:underscore-99xp_project:underscore-99xp:1.7.2:*:*:*:*:node.js:*:*

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