How severe is CVE-2020-8201?

CVE-2020-8201 has a CVSS 3.x base score of 7.4, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2020-8201 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (91st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-8201?

CVE-2020-8201 primarily affects Nodejs Node.js. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-8201?

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-2020-8201 published?

CVE-2020-8201 was published on 2020-09-18 and last updated on 2026-06-17.

CVE-2020-8201

Q: What is CVE-2020-8201?

Node.js < 12.18.4 and < 14.11 can be exploited to perform HTTP desync attacks and deliver malicious payloads to unsuspecting users. The payloads can be crafted by an attacker to hijack user sessions, poison cookies, perform clickjacking, and a multitude of other attacks depending on the architecture of the underlying system. The attack was possible due to a bug in processing of carrier-return symbols in the HTTP header names.

CVE-2020-8201 is a high-severity vulnerability in Nodejs Node.js with a CVSS 3.x base score of 7.4. 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-444.

Key facts

Severity: High (CVSS 3.x base score 7.4)
CVSS v2: 5.8
EPSS exploit prediction: 5% (91st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-444
Affected product: Nodejs Node.js
Published: 2020-09-18
Last modified: 2026-06-17

Description

Node.js < 12.18.4 and < 14.11 can be exploited to perform HTTP desync attacks and deliver malicious payloads to unsuspecting users. The payloads can be crafted by an attacker to hijack user sessions, poison cookies, perform clickjacking, and a multitude of other attacks depending on the architecture of the underlying system. The attack was possible due to a bug in processing of carrier-return symbols in the HTTP header names.

Frequently asked questions

What is CVE-2020-8201?: Node.js < 12.18.4 and < 14.11 can be exploited to perform HTTP desync attacks and deliver malicious payloads to unsuspecting users. The payloads can be crafted by an attacker to hijack user sessions, poison cookies, perform clickjacking, and a multitude of other attacks depending on the architecture of the underlying system. The attack was possible due to a bug in processing of carrier-return symbols in the HTTP header names.
How severe is CVE-2020-8201?: CVE-2020-8201 has a CVSS 3.x base score of 7.4, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2020-8201 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (91st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-8201?: CVE-2020-8201 primarily affects Nodejs Node.js. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-8201?: 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-2020-8201 published?: CVE-2020-8201 was published on 2020-09-18 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:a:nodejs:node.js:*:*:*:*:lts:*:*:*
cpe:2.3:a:nodejs:node.js:*:*:*:*:*:*:*:*
cpe:2.3:o:opensuse:leap:15.2:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*

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