Fastify's Content-Type header tab character allows body validation bypass

Summary

CVECVE-2026-25223
StatePUBLISHED
AssignerGitHub_M
Source PriorityCVE Program / NVD first with legacy fallback
Published2026-02-03 22:16:31 UTC
Updated2026-07-15 02:18:52 UTC
DescriptionFastify is a fast and low overhead web framework, for Node.js. Prior to version 5.7.2, a validation bypass vulnerability exists in Fastify where request body validation schemas specified by Content-Type can be completely circumvented. By appending a tab character (\t) followed by arbitrary content to the Content-Type header, attackers can bypass body validation while the server still processes the body as the original content type. This issue has been patched in version 5.7.2.

Risk And Classification

Primary CVSS: v3.1 7.5 HIGH from ADP

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

EPSS: 0.007700000 probability, percentile 0.515250000 (date 2026-07-18)

Problem Types: CWE-436 | CWE-179 | CWE-436 CWE-436: Interpretation Conflict | CWE-179 Incorrect Behavior Order: Early Validation


VersionSourceTypeScoreSeverityVector
3.1ADPCVSS7.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
3.1[email protected]Secondary7.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
3.10b0ca135-0b70-47e7-9f44-1890c2a1c46cSecondary7.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
3.1CNADECLARED7.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

CVSS v3.1 Breakdown

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
High
Availability
None

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Application Fastify Fastify All All All All

Vendor Declared Affected Products

SourceVendorProductVersionPlatforms
CNA Fastify Fastify affected < 5.7.2 Not specified
ADP Red Hat Red Hat OpenShift AI 2.16 unaffected 1774282136 * rpm Not specified
ADP Red Hat Red Hat OpenShift AI 2.25 unaffected 1776742021 * rpm Not specified
ADP Red Hat Red Hat OpenShift AI 2.25 unaffected 1776742141 * rpm Not specified
ADP Red Hat Red Hat OpenShift Dev Spaces 3.27 unaffected 1774476526 * rpm Not specified
ADP Red Hat Red Hat Enterprise Linux AI RHEL AI 3 Not specified Not specified
ADP Red Hat Red Hat Enterprise Linux AI RHEL AI 3 Not specified Not specified
ADP Red Hat Red Hat OpenShift AI RHOAI Not specified Not specified

References

ReferenceSourceLinkTags
access.redhat.com/errata/RHSA-2026:5807 0b0ca135-0b70-47e7-9f44-1890c2a1c46c access.redhat.com
github.com/fastify/fastify/blob/759e9787b5669abf953068e42a17bffba7521348... [email protected] github.com Product
security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-25223.json 0b0ca135-0b70-47e7-9f44-1890c2a1c46c security.access.redhat.com
access.redhat.com/errata/RHSA-2026:10184 0b0ca135-0b70-47e7-9f44-1890c2a1c46c access.redhat.com
bugzilla.redhat.com/show_bug.cgi 0b0ca135-0b70-47e7-9f44-1890c2a1c46c bugzilla.redhat.com
github.com/fastify/fastify/commit/32d7b6add39ddf082d92579a58bea7018c5ac821 [email protected] github.com Patch
hackerone.com/reports/3464114 [email protected] hackerone.com Permissions Required
github.com/fastify/fastify/blob/759e9787b5669abf953068e42a17bffba7521348... [email protected] github.com Product
fastify.dev/docs/latest/Reference/Validation-and-Serialization [email protected] fastify.dev Product, Technical Description
github.com/fastify/fastify/security/advisories/GHSA-jx2c-rxcm-jvmq [email protected] github.com Mitigation, Vendor Advisory
access.redhat.com/errata/RHSA-2026:6192 0b0ca135-0b70-47e7-9f44-1890c2a1c46c access.redhat.com
access.redhat.com/security/cve/CVE-2026-25223 0b0ca135-0b70-47e7-9f44-1890c2a1c46c access.redhat.com
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Additional Advisory Data

SourceTimeEvent
ADP2026-02-03T22:01:19.884ZReported to Red Hat.
ADP2026-02-03T21:21:40.268ZMade public.

Solutions

ADP: RHSA-2026:5807: Red Hat OpenShift AI 2.16

ADP: RHSA-2026:10184: Red Hat OpenShift AI 2.25

ADP: RHSA-2026:6192: Red Hat OpenShift Dev Spaces 3.27

Workarounds

ADP: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.

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