CVE-2020-5207

Request smuggling is possible in Ktor when both chunked TE and content length specified

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Published Jan 27, 2020 CVSS 3.1 · 5.4 Medium EPSS < 1% KEV · Not listed

Description

In Ktor before 1.3.0, request smuggling is possible when running behind a proxy that doesn't handle Content-Length and Transfer-Encoding properly or doesn't handle \n as a headers separator.

Affected Products

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

Ktor.io

Ktor

affected

Version	Status	Constraints
`< 1.3.0`	affected	—

Configuration 1 [-]

cpe:2.3:a:jetbrains:ktor:*:*:*:*:*:*:*:*

No data.

No data available yet.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source	ID	Title
Github GHSA	GHSA-xrr9-rh8p-433v	Request smuggling is possible when both chunked TE and content length specified

Metrics

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required Low

Scope Changed

Confidentiality Impact Low

Integrity Impact Low

Availability Impact None

User Interaction Required

No CVSS v3.0

Access Vector Network

Access Complexity Low

Authentication None

Confidentiality Impact None

Integrity Impact Partial

Availability Impact None

This CVE is not in the KEV list.

Exploit prediction score: < 1% (0.762% probability within 30 days)

Key SSVC decision points have not yet been added.

References

Link	Providers
https://github.com/ktorio/ktor/pull/1547
https://github.com/ktorio/ktor/security/advisories/GHSA-xrr9-rh8p-433v

History

No history.

Subscriptions

Jetbrains Ktor

Weaknesses

CWE-444

Sources

CVE record Updated: Aug 4, 2024, 8:22 AM

Status: PUBLISHED
Assigner: GitHub_M
Published: Jan 27, 2020, 7:30 PM
Updated: Aug 4, 2024, 8:22 AM
Reserved: Jan 2, 2020, 12:00 AM

View source JSON

Vulnrichment No data

No data.

NVD Updated: Jun 17, 2026, 3:21 AM

Status: Modified
Published: Jan 27, 2020, 8:15 PM
Modified: Jun 17, 2026, 3:21 AM

View source JSON

Red Hat No data

No data.

OpenCVE enrichment No data

No data.

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