How severe is CVE-2021-27515?

CVE-2021-27515 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2021-27515 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-27515?

CVE-2021-27515 affects Url-parse Project Url-parse. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-27515?

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

When was CVE-2021-27515 published?

CVE-2021-27515 was published on 2021-02-22 and last updated on 2026-06-17.

CVE-2021-27515

CVE-2021-27515 is a medium-severity vulnerability in Url-parse Project Url-parse with a CVSS 3.x base score of 5.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 5.0
EPSS exploit prediction: 2% (78th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Url-parse Project Url-parse
Published: 2021-02-22
Last modified: 2026-06-17

Description

url-parse before 1.5.0 mishandles certain uses of backslash such as http:\/ and interprets the URI as a relative path.

Frequently asked questions

What is CVE-2021-27515?: url-parse before 1.5.0 mishandles certain uses of backslash such as http:\/ and interprets the URI as a relative path.
How severe is CVE-2021-27515?: CVE-2021-27515 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2021-27515 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-27515?: CVE-2021-27515 affects Url-parse Project Url-parse. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-27515?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-27515 published?: CVE-2021-27515 was published on 2021-02-22 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:url-parse_project:url-parse:*:*:*:*:*:node.js:*:*

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