How severe is CVE-2020-26311?

CVE-2020-26311 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-2020-26311 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (39th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-26311?

CVE-2020-26311 affects Useragent Project Useragent. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-26311?

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.

Does CVE-2020-26311 have an EU (EUVD) identifier?

Yes. CVE-2020-26311 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-3081.

When was CVE-2020-26311 published?

CVE-2020-26311 was published on 2024-10-26 and last updated on 2026-06-17.

CVE-2020-26311

CVE-2020-26311 is a high-severity vulnerability in Useragent Project Useragent 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 v4: 8.7
EPSS exploit prediction: 0% (39th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-3081
Weakness: CWE-1333
Affected product: Useragent Project Useragent
Published: 2024-10-26
Last modified: 2026-06-17

Description

Useragent is a user agent parser for Node.js. All versions as of time of publication contain one or more regular expressions that are vulnerable to Regular Expression Denial of Service (ReDoS). As of time of publication, no patches are available.

Frequently asked questions

What is CVE-2020-26311?: Useragent is a user agent parser for Node.js. All versions as of time of publication contain one or more regular expressions that are vulnerable to Regular Expression Denial of Service (ReDoS). As of time of publication, no patches are available.
How severe is CVE-2020-26311?: CVE-2020-26311 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-2020-26311 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (39th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-26311?: CVE-2020-26311 affects Useragent Project Useragent. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-26311?: 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.
Does CVE-2020-26311 have an EU (EUVD) identifier?: Yes. CVE-2020-26311 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-3081.
When was CVE-2020-26311 published?: CVE-2020-26311 was published on 2024-10-26 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:useragent_project:useragent:*:*:*:*:*:node.js:*:*

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