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CVE Record

CVE-2020-27218: In Eclipse Jetty version 9.4.0.RC0 to 9.4.34.v20201102, 10.0.0.alpha0 to 10.0.0.beta2, and 11.0.0.alpha0 to...

In Eclipse Jetty version 9.4.0.RC0 to 9.4.34.v20201102, 10.0.0.alpha0 to 10.0.0.beta2, and 11.0.0.alpha0 to 11.0.0.beta2, if GZIP request body inflation is enabled and requests from different clients are multiplexed onto a single connection, and if an attacker can send a request with a body that is received entirely but not consumed by the application, then a subsequent request on the same connection will see that body prepended to its body. The attacker will not see any data but may inject data into the body of the subsequent request.

UnknownCVSS not scoredNot KEV-listedUpdated
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Glexia's TakeAutomated analysismoderate

Security readout for executives and security teams

Plain-English summary

CVE-2020-27218 affects Eclipse Jetty when compressed request-body inflation is enabled and different clients share one multiplexed connection. Under those conditions, an attacker may cause their unconsumed request body to be prepended to a later client request. This is request-body injection risk, not evidence that attackers can read another user's data.

Executive priority

Treat this as a targeted dependency remediation item, not a broad emergency based on the provided evidence. Prioritize internet-facing or sensitive Jetty services, especially where compressed request bodies and multiplexed upstream connections are present.

Technical view

Affected Jetty ranges are 9.4.0.RC0 through 9.4.34.v20201102, 10.0.0.alpha0 through 10.0.0.beta2, and 11.0.0.alpha0 through 11.0.0.beta2. The issue requires GZIP request inflation, multiplexed requests from different clients on one connection, and an application that receives but does not consume a request body.

Likely exposure

Exposure is most likely in applications embedding Jetty within the listed versions and accepting compressed request bodies over multiplexed connections. Risk depends on reverse proxies, HTTP protocol handling, and application behavior around unread request bodies.

Exploitation context

The source bundle does not show CISA KEV listing or cited active exploitation. Exploitation appears condition-dependent and may allow request-body injection into a subsequent request, but the attacker is not described as seeing the victim's data.

Researcher notes

Key validation hinges on runtime conditions, not version alone. Confirm Jetty version, gzip request inflation, upstream connection reuse or multiplexing, and handlers that leave bodies unread. The bundle provides no CVSS vector, no KEV status, and no confirmed exploitation evidence.

Mitigation direction

  • Inventory applications and dependencies using Eclipse Jetty in the affected ranges.
  • Review the Eclipse Jetty advisory and apply vendor-recommended fixed releases or configuration changes.
  • Assess whether GZIP request body inflation is enabled and needed in exposed services.
  • Review front-end proxy behavior for request multiplexing across different clients.
  • Prioritize externally reachable Jetty services that process sensitive request bodies.

Validation and detection

  • Confirm the deployed Jetty version for each application and transitive dependency.
  • Check configuration for GZIP request body inflation support.
  • Identify whether client requests can be multiplexed onto shared upstream Jetty connections.
  • Review application handlers for request bodies received but not fully consumed.
  • Use dependency scanning to confirm vulnerable Jetty versions are no longer present.
Prepared
Confidence
medium
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

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cwe · low confidence lookup

CWE-226: Exact CWE lookup

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CVE-2020-27218 mapping review

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Vulnerability profileCVE Program record
Severity
Unknown
CVSS
Not scored
Known Exploited
No
Published
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.

0CVSS vectors
0Timeline events
0ADP providers
41Source links

CVSS and timeline data

No CVSS vectors or timeline events were available in the normalized CVE source material.

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
The Eclipse FoundationEclipse Jetty9.4.0.RC0 to 9.4.34.v20201102, 10.0.0.alpha0 to 10.0.0.beta2, 11.0.0.alpha0 to 11.0.0.beta2Listed
Weakness

CWE details

CWE-226

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Sensitive Information in Resource Not Removed Before Reuse

Sensitive Information in Resource Not Removed Before Reuse represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.

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