CVE-2024-39694Network attack vector

Open redirect via control-character URL validation

Published Jul 31, 2024 · Updated Jul 31, 2024

Open redirect in affected Duende IdentityServer releases allows remote attackers to redirect users to untrusted sites through malicious URLs. StringsExtensions.IsLocalUrl accepts paths containing ASCII control characters, causing interaction services and parsers to treat external URLs as local. Exposure requires host UI code to redirect the returned URL and a browser that follows it; the flaw alone does not disclose credentials or tokens.

CVSS severity4.7
Medium
EPSS probability0.53%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Open redirect in affected Duende IdentityServer releases allows remote attackers to redirect users to untrusted sites through malicious URLs. StringsExtensions.IsLocalUrl accepts paths containing ASCII control characters, causing interaction services and parsers to treat external URLs as local. Exposure requires host UI code to redirect the returned URL and a browser that follows it; the flaw alone does not disclose credentials or tokens.

The record

CVE
CVE-2024-39694
Published
Jul 31, 2024
Updated
Jul 31, 2024
Vendor
Duende Software
Product
Duende IdentityServer
Classifications
CWE-601
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 31, 2024CVE publishedPublication date reported by the CVE source.
  2. Jul 31, 2024Record 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=< 6.0.5
  2. Affected versionversion=>= 6.1.0-preview.1, <= 6.1.7
  3. Affected versionversion=>= 6.2.0-preview.1, <= 6.2.4
  4. Affected versionversion=>= 6.3.0-preview.1, <= 6.3.9
  5. Affected versionversion=>= 7.0.0-preview.1, <= 7.0.5

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Duende Software · Duende IdentityServerversion=< 6.0.5; version=>= 6.1.0-preview.1, <= 6.1.7; version=>= 6.2.0-preview.1, <= 6.2.4; version=>= 6.3.0-preview.1, <= 6.3.9; version=>= 7.0.0-preview.1, <= 7.0.5

Published CVSS scores

4.7GitHub CNACVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-601URL Redirection to Untrusted Site ('Open Redirect')

Public exploit references

No public exploit references are available in this record.

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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