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CVE Record

CVE-2021-34429: For Eclipse Jetty versions 9.4.37-9.4.42, 10.0.1-10.0.5 & 11.0.1-11.0.5, URIs can be crafted using some enc...

For Eclipse Jetty versions 9.4.37-9.4.42, 10.0.1-10.0.5 & 11.0.1-11.0.5, URIs can be crafted using some encoded characters to access the content of the WEB-INF directory and/or bypass some security constraints. This is a variation of the vulnerability reported in CVE-2021-28164/GHSA-v7ff-8wcx-gmc5.

MediumCVSS 5.3Not KEV-listedUpdated
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Glexia's TakeAutomated analysismoderate

Security readout for executives and security teams

Plain-English summary

This Jetty flaw can let a remote unauthenticated user reach files or routes that should be hidden when an application runs affected Jetty versions. The known impact is limited confidentiality exposure, not code execution. Treat it as moderate urgency for internet-facing Java services and embedded products that bundle Jetty.

Executive priority

Prioritize remediation where Jetty is internet-facing, protects sensitive application resources, or ships inside business-critical platforms. This is not presented as emergency code execution, but it can undermine access boundaries and disclose internal application content.

Technical view

CVE-2021-34429 affects Eclipse Jetty 9.4.37-9.4.42, 10.0.1-10.0.5, and 11.0.1-11.0.5. Crafted URIs using encoded characters may expose WEB-INF content or bypass security constraints. It is described as a variation of CVE-2021-28164 and maps to CWE-200 and CWE-551.

Likely exposure

Exposure is most likely in Java applications, management interfaces, or third-party platforms embedding affected Jetty releases. The references show downstream attention in Apache ZooKeeper, Pulsar, Kafka, and Santuario, so transitive dependency inventory matters.

Exploitation context

The provided sources do not show CISA KEV listing or confirmed active exploitation. The CVSS vector indicates remote, unauthenticated, low-complexity access with low confidentiality impact and no stated integrity or availability impact.

Researcher notes

Focus analysis on URI normalization, encoded character handling, WEB-INF resource exposure, and security-constraint bypass behavior. Evidence supports affected Jetty ranges and downstream upgrades, but the bundle does not include detailed proof-of-concept mechanics or active exploitation evidence.

Mitigation direction

  • Upgrade Jetty to a vendor-supported version outside the affected ranges.
  • For Jetty 9.4.x, cited downstream projects moved to 9.4.43.v20210629.
  • Check the Eclipse Jetty advisory before selecting 10.x or 11.x target versions.
  • Update third-party products that bundle vulnerable Jetty versions.
  • Retest route protections and packaged resource access after upgrading.

Validation and detection

  • Inventory direct and transitive Jetty versions across applications and packaged products.
  • Flag Jetty 9.4.37-9.4.42, 10.0.1-10.0.5, and 11.0.1-11.0.5.
  • Review logs for unusual encoded-character requests against protected paths.
  • Confirm WEB-INF content is not reachable through authorized regression testing.
  • Verify security constraints still apply after dependency upgrades.
Prepared
Confidence
high
Sources
8

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 · medium confidence lookup

CWE-200: Information exposure and cloud metadata lookup

Information exposure and SSRF weaknesses can make discovery, cloud metadata, and credential material review relevant. 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.

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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.

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cve · low confidence lookup

CVE-2021-34429 mapping review

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

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Vulnerability profileCVE Program record
Severity
Medium
CVSS
5.3 (3.1)
Known Exploited
No
Published

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

1CVSS vectors
0Timeline events
0ADP providers
39Source links

CVSS vector scores

1 official score

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
5.3CVSS 3.1MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N3.91.4Primary CVE score

Vulnerability scoring details

Base CVSS 3.1 score

5.3Medium
CVSS 3.1 vector shape for CVE-2021-34429Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

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

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Privileges Required
NoneLowHigh
User Interaction
NoneRequired
Scope
ChangedUnchanged
Confidentiality Impact
HighLowNone
Integrity Impact
HighLowNone
Availability Impact
HighLowNone

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
The Eclipse FoundationEclipse Jetty9.4.37, unspecified, 10.0.1, unspecified, 11.0.1, unspecifiedListed
Weakness

CWE details

CWE-200CWE-551

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

CWE-200 · source CWE mapping

Exposure of Sensitive Information to an Unauthorized Actor

Exposure of Sensitive Information to an Unauthorized Actor represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.

Open CWE intelligenceSame-CWE CVEs
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