CVE-2026-110354 (GCVE-0-2026-110354)

Vulnerability from cvelistv5 – Published: 2026-10-22 02:46 – Updated: 2026-10-22 02:46
VLAI
Summary
HAProxy 3 before 3.4.6 allows a remote unauthenticated attacker to cause a denial of service (persistent worker-thread CPU exhaustion) via an HTTP/1.1 chunked request. Although the H1 multiplexer drains the request before closing the stream, the parser repeatedly re-processes the same bytes without making progress. The affected thread stays busy at 100% CPU after timeouts expire and after the client disconnects, and repeated requests can consume all worker threads until the process is restarted.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
  • CWE-835 - Loop with Unreachable Exit Condition ('Infinite Loop')
Assigner
mitre CNA under the mitre root
CNA scorecard E 29/100 over 2359 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
HAProxy HAProxy Affected: 3.0.0 , < 3.0.30 (custom)
Affected: 3.2.0 , < 3.2.26 (custom)
Affected: 3.3.0 , < 3.3.17 (custom)
Affected: 3.4.0 , < 3.4.6 (custom)
Affected: 3.5-dev , < 3.5-dev9 (custom)
guessed Create a notification for this product.
HAProxy HAProxy Enterprise Edition Affected: 3.0r1 , < 3.0r1-362.1441 (custom)
Affected: 3.2r1 , < 3.2r1-378.1259 (custom)
Affected: 3.3r1 , < 3.3r1-377.1005 (custom)
guessed Create a notification for this product.
HAProxy Technologies HAProxy Kubernetes Ingress Controller Affected: 3.2.0 , < 3.2.17 (custom)
guessed Create a notification for this product.
HAProxy Technologies Kubernetes Ingress Controller Enterprise Affected: 3.2.0 , < 3.2.17-ee1 (custom)
Affected: 3.0 , < 3.0.16-ee17 (custom)
Affected: 1.11 , < 1.11.14-ee11 (custom)
guessed Create a notification for this product.
Show details on NVD website
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{
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          "modules": [
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          "programFiles": [
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            }
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      "providerMetadata": {
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    "datePublished": "2026-10-22T02:46:38.255Z",
    "dateReserved": "2026-10-13T23:22:44.319Z",
    "dateUpdated": "2026-10-22T02:46:38.255Z",
    "state": "PUBLISHED"
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                "modules": [
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                ],
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                "programFiles": [
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                ],
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        "lastModified": "2026-10-22T17:36:46.950",
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      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-110354.json",
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}



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