CVE-2019-15606Network attack vector

Authorization bypass via untrimmed HTTP header whitespace

Published Feb 7, 2020 · Updated Apr 30, 2025

Improper HTTP parsing in Node.js allows remote attackers to bypass header-based authorization checks with trailing whitespace. The HTTP parser passes header values to application code without stripping trailing optional whitespace, so exact comparisons can interpret equivalent values differently. Affected servers are exposed only when authorization logic relies on an exact parsed header value, allowing access that the comparison was intended to deny.

CVSS severity9.8
Critical
EPSS probability20.04%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper HTTP parsing in Node.js allows remote attackers to bypass header-based authorization checks with trailing whitespace. The HTTP parser passes header values to application code without stripping trailing optional whitespace, so exact comparisons can interpret equivalent values differently. Affected servers are exposed only when authorization logic relies on an exact parsed header value, allowing access that the comparison was intended to deny.

The record

CVE
CVE-2019-15606
Published
Feb 7, 2020
Updated
Apr 30, 2025
Vendor
Node.js
Product
Node.js
Classifications
T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 7, 2020CVE publishedPublication date reported by the CVE source.
  2. Apr 30, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=10.0 <10.19.0
  2. Affected versionversion=11.0 <11.*
  3. Affected versionversion=12.0 <12.15.0
  4. Affected versionversion=13.0 <13.8.0
  5. Affected versionversion=4.0 <4.*
  6. Affected versionversion=5.0 <5.*
  7. Affected versionversion=6.0 <6.*
  8. Affected versionversion=7.0 <7.*
  9. Affected versionversion=8.0 <8.*
  10. Affected versionversion=9.0 <9.*

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Node.js · Node.jsversion=10.0 <10.19.0; version=11.0 <11.*; version=12.0 <12.15.0; version=13.0 <13.8.0; version=4.0 <4.*; version=5.0 <5.*; version=6.0 <6.*; version=7.0 <7.*; version=8.0 <8.*; version=9.0 <9.*

Published CVSS scores

9.8NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
7.5NVDAV:N/AC:L/Au:N/C:P/I:P/A:P

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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