How severe is CVE-2020-7662?

CVE-2020-7662 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-2020-7662 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-7662?

CVE-2020-7662 affects Websocket-extensions Project Websocket-extensions. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-7662?

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-2020-7662 published?

CVE-2020-7662 was published on 2020-06-02 and last updated on 2026-06-17.

CVE-2020-7662

CVE-2020-7662 is a high-severity vulnerability in Websocket-extensions Project Websocket-extensions 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.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 3% (86th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Websocket-extensions Project Websocket-extensions
Published: 2020-06-02
Last modified: 2026-06-17

Description

websocket-extensions npm module prior to 0.1.4 allows Denial of Service (DoS) via Regex Backtracking. The extension parser may take quadratic time when parsing a header containing an unclosed string parameter value whose content is a repeating two-byte sequence of a backslash and some other character. This could be abused by an attacker to conduct Regex Denial Of Service (ReDoS) on a single-threaded server by providing a malicious payload with the Sec-WebSocket-Extensions header.

Frequently asked questions

What is CVE-2020-7662?: websocket-extensions npm module prior to 0.1.4 allows Denial of Service (DoS) via Regex Backtracking. The extension parser may take quadratic time when parsing a header containing an unclosed string parameter value whose content is a repeating two-byte sequence of a backslash and some other character. This could be abused by an attacker to conduct Regex Denial Of Service (ReDoS) on a single-threaded server by providing a malicious payload with the Sec-WebSocket-Extensions header.
How severe is CVE-2020-7662?: CVE-2020-7662 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-2020-7662 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-7662?: CVE-2020-7662 affects Websocket-extensions Project Websocket-extensions. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-7662?: 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-2020-7662 published?: CVE-2020-7662 was published on 2020-06-02 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:websocket-extensions_project:websocket-extensions:*:*:*:*:*:node.js:*:*

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