CVE-2023-47124Network attack vector

Service interruption via HTTPChallenge retry backoff

Published Dec 4, 2023 · Updated Dec 18, 2024

Resource exhaustion in Traefik Proxy before 2.10.6 and 3.0.0-beta1 through 3.0.0-beta4 allows remote attackers to interrupt service. The ACME HTTPChallenge handler applies a 50-second retry backoff even though its Present method is synchronous, allowing slow requests to retain resources. Exposure requires HTTPChallenge configuration on an Internet-reachable port 80 entry point; sustained slow connections can exhaust service capacity.

CVSS severity5.9
Medium
EPSS probability0.79%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Resource exhaustion in Traefik Proxy before 2.10.6 and 3.0.0-beta1 through 3.0.0-beta4 allows remote attackers to interrupt service. The ACME HTTPChallenge handler applies a 50-second retry backoff even though its Present method is synchronous, allowing slow requests to retain resources. Exposure requires HTTPChallenge configuration on an Internet-reachable port 80 entry point; sustained slow connections can exhaust service capacity.

The record

CVE
CVE-2023-47124
Published
Dec 4, 2023
Updated
Dec 18, 2024
Vendor
Traefik Labs
Product
Traefik Proxy
Classifications
CWE-772, T1499.003
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 4, 2023CVE publishedPublication date reported by the CVE source.
  2. Dec 18, 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=< 2.10.6
  2. Affected versionversion=>= 3.0.0-beta1, < 3.0.0-beta5

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Traefik Labs · Traefik Proxyversion=< 2.10.6; version=>= 3.0.0-beta1, < 3.0.0-beta5

Published CVSS scores

5.9GitHub, Inc.CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

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

Weakness, pattern, technique

CWE-772Missing Release of Resource after Effective Lifetime
T1499.003Application Exhaustion Flood

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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