How severe is CVE-2021-36716?

CVE-2021-36716 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-2021-36716 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-2021-36716?

CVE-2021-36716 affects Segment Is-email. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-36716?

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-2021-36716 published?

CVE-2021-36716 was published on 2021-07-14 and last updated on 2026-06-17.

CVE-2021-36716

CVE-2021-36716 is a high-severity vulnerability in Segment Is-email 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-400.

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-400
Affected product: Segment Is-email
Published: 2021-07-14
Last modified: 2026-06-17

Description

A ReDoS (regular expression denial of service) flaw was found in the Segment is-email package before 1.0.1 for Node.js. An attacker that is able to provide crafted input to the isEmail(input) function may cause an application to consume an excessive amount of CPU.

Frequently asked questions

What is CVE-2021-36716?: A ReDoS (regular expression denial of service) flaw was found in the Segment is-email package before 1.0.1 for Node.js. An attacker that is able to provide crafted input to the isEmail(input) function may cause an application to consume an excessive amount of CPU.
How severe is CVE-2021-36716?: CVE-2021-36716 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-2021-36716 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-2021-36716?: CVE-2021-36716 affects Segment Is-email. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-36716?: 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-2021-36716 published?: CVE-2021-36716 was published on 2021-07-14 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:segment:is-email:*:*:*:*:*:node.js:*:*

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