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CVE Record

CVE-2026-39852: Quarkus authorization bypass via semicolon path normalization inconsistency

Quarkus is a Java framework for building cloud-native applications. In versions prior to 3.20.6.1, 3.27.3.1, 3.33.1.1, 3.35.1.1, 3.34.7, and 3.35.2, a path normalization inconsistency between the security layer and the routing layer allows unauthenticated or lower-privileged users to bypass HTTP path-based authorization policies. Quarkus's security layer performs authorization checks on the raw URL path which preserves matrix parameters (semicolons), while RESTEasy Reactive's routing layer strips matrix parameters before matching endpoints. An attacker can append a semicolon and arbitrary text to a request URL (e.g., /api/admin;anything) to bypass policies protecting /api/admin while still routing to the protected endpoint. This issue has been fixed in versions 3.20.6.1, 3.27.3.1, 3.33.1.1, 3.35.1.1, 3.34.7, and 3.35.2.

HighCVSS 8.8Not KEV-listedUpdated
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Glexia's TakeAutomated analysishigh

Security readout for executives and security teams

Plain-English summary

Affected Quarkus applications may let unauthenticated or lower-privileged users reach protected HTTP endpoints. A semicolon in a request path can make authorization evaluate a different path from the one ultimately routed, potentially exposing sensitive data or privileged operations.

Executive priority

Prioritize rapid remediation for externally reachable applications protecting administrative, financial, personal, or other sensitive functions through path rules. Internal-only systems should still be inventoried and upgraded according to exposure and data sensitivity.

Technical view

Quarkus security checks the raw URL path while RESTEasy Reactive removes matrix parameters before endpoint matching. This normalization mismatch can cause a modified path to evade a path-based authorization rule yet resolve to the protected endpoint. The supplied CVSS 4.0 score is 8.8.

Likely exposure

Exposure requires a vulnerable Quarkus version, RESTEasy Reactive routing, and HTTP path-based authorization policies. Internet-facing administrative or sensitive endpoints increase business risk. The bundle does not establish how commonly affected configurations are deployed.

Exploitation context

The described bypass is network-accessible, low-complexity, requires no privileges or user interaction, and can affect confidentiality and integrity. The CVE is not listed as KEV, and the supplied sources provide no evidence of active exploitation.

Researcher notes

The issue maps to CWE-551 and CWE-863. Supplied fixed versions are 3.20.6.1, 3.27.3.1, 3.33.1.1, 3.34.7, 3.35.1.1, and 3.35.2. Confirm branch-specific applicability with vendor guidance because the supplied affected ranges do not enumerate every fixed branch.

Mitigation direction

  • Upgrade to an applicable fixed Quarkus release identified by the vendor advisory.
  • Apply the relevant Red Hat erratum when using a Red Hat-distributed affected product.
  • Restrict external access to sensitive endpoints until upgrades are completed.
  • Monitor protected routes for unexpected semicolon-bearing request paths.

Validation and detection

  • Inventory Quarkus versions across applications and compare them with the supplied affected ranges.
  • Identify applications using RESTEasy Reactive with path-based authorization policies.
  • Confirm deployed artifacts use an applicable fixed release after remediation.
  • Review access logs for semicolon-bearing requests targeting sensitive or administrative routes.
  • Retest authorization boundaries defensively after upgrading.
Prepared
Confidence
high
Sources
5

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.

cwe · low confidence lookup

CWE-551: Exact CWE lookup

Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.

Open ATT&CK lookup
cwe · medium confidence lookup

CWE-863: Authorization and privilege behavior lookup

Authorization weaknesses can support privilege escalation and valid-account review, depending on exploit path. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.

Open ATT&CK lookup
description · low confidence lookup

Privilege behavior lookup

The CVE wording references privilege impact, so privilege escalation and authorization behavior review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.

Open ATT&CK lookup
cve · low confidence lookup

CVE-2026-39852 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

Open ATT&CK lookup
Vulnerability profileCVE Program record
Severity
High
CVSS
8.8 (4.0)
Known Exploited
No
Published

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N

Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

2CVSS vectors
5Timeline events
2ADP providers
12Source links

SSVC decision data

CISA-ADPCISA Coordinator
Timestamp
Version
2.0.3
Exploitation: noneAutomatable: noTechnical Impact: partial

CVSS vector scores

2 official scores

We collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.

ScoreVersionSeverityVectorExploitImpactSource
8.8CVSS 4.0HighCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N——GitHub_M
8.2CVSS 3.1HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H3.94.2redhat-SADP

Vulnerability scoring details

Base CVSS 4.0 score

8.8High
CVSS 4.0 vector shape for CVE-2026-39852Attack VectorAttack ComplexityAttack RequirementsPrivileges RequiredUser InteractionVS ConfidentialityVS IntegrityVS AvailabilitySS ConfidentialitySS IntegritySS Availability

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Attack Requirements
NonePresent
Privileges Required
NoneLowHigh
User Interaction
NonePassiveActive
VS Confidentiality
HighLowNone
VS Integrity
HighLowNone
VS Availability
HighLowNone
SS Confidentiality
HighLowNone
SS Integrity
HighLowNone
SS Availability
HighLowNone

Vulnerability timeline

Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.

  1. CVE reservedCVE Program

    The CVE ID was reserved by the assigning CNA.

  2. ADP timelineredhat-SADP

    Reported to Red Hat.

  3. ADP timelineredhat-SADP

    Made public.

  4. CVE publishedCVE Program

    The CVE record was published.

  5. CVE updatedCVE Program

    The CVE record metadata indicates this as the latest update time.

ADP provider summaries

CISA-ADPCISA ADP Vulnrichment
other:ssvc
redhat-SADPio.quarkus:quarkus-vertx-http: io.quarkus:quarkus-vertx-http: Authorization bypass via semicolons in HTTP requests
other:Red Hat severity ratingcvssV3_1
  • 2026-04-13T13:26:46.572Z: Reported to Red Hat.
  • 2026-05-04T00:00:00.000Z: Made public.

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
quarkusioquarkus< 3.20.6.1, >= 3.27.3.0, < 3.27.3.1, >= 3.34.0, < 3.34.7, >= 3.35.0, < 3.35.2Listed
Weakness

CWE details

CWE-551CWE-863

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.

CWE-551 · source CWE mapping

Incorrect Behavior Order: Authorization Before Parsing and Canonicalization

Incorrect Behavior Order: Authorization Before Parsing and Canonicalization represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.

Open CWE intelligenceSame-CWE CVEs
CWE-863 · source CWE mapping

Incorrect Authorization

Incorrect Authorization represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.

Open CWE intelligenceSame-CWE CVEs