CVE-2026-66754

Rouille 0.1.6 - 3.6.2 Reachable Assertion DoS via remove_prefix percent-encoding

Published Jul 28, 2026 · Updated Jul 29, 2026

Rouille 0.1.6 through 3.6.2 contains a reachable assertion vulnerability in the Request::remove_prefix function that allows remote unauthenticated attackers to crash the server by sending a crafted percent-encoded URL. Attackers can send a request whose decoded path matches a configured prefix while the raw percent-encoded path does not, causing the assert! to fail and triggering either a 500 error or full process termination depending on the panic configuration.

CVSS severityUnavailable
Unscored
EPSS probability0.40%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Rouille 0.1.6 through 3.6.2 contains a reachable assertion vulnerability in the Request::remove_prefix function that allows remote unauthenticated attackers to crash the server by sending a crafted percent-encoded URL. Attackers can send a request whose decoded path matches a configured prefix while the raw percent-encoded path does not, causing the assert! to fail and triggering either a 500 error or full process termination depending on the panic configuration.

The record

CVE
CVE-2026-66754
Published
Jul 28, 2026
Updated
Jul 29, 2026
Vendor
tomaka
Product
Rouille
Classifications
Unavailable
Attack vector
Unavailable
Privileges
Unavailable

Timeline

How it unfolded

  1. Jul 28, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 29, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0.1.6 <=3.6.2

What conditions does exploitation require?

Attack vectorUnavailable in this record.
Required privilegesUnavailable in this record.

What is affected?

tomaka · Rouilleversion=0.1.6 <=3.6.2

Published CVSS scores

No CVSS assessment is available in this record.

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
VectorUnavailable
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

No sourced classifications are available.

Public exploit references

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Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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