CVE-2026-54571

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Source
https://cve.org/CVERecord?id=CVE-2026-54571
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-54571.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-54571
Aliases
  • GHSA-4phx-fcj6-46r4
Published
2026-09-17T18:28:26Z
Modified
2026-09-19T08:08:54Z
Severity
  • 8.7 (High) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N CVSS Calculator
Summary
ESPAsyncWebServer: Integer overflow in multipart boundary parser causes denial of service
Details

ESPAsyncWebServer is an asynchronous HTTP and WebSocket server library for ESP32, ESP8266, RP2040 and RP2350. Prior to 3.11.1, the multipart/form-data parser in src/WebRequest.cpp stores _boundaryPosition as an 8-bit value while _parseMultipartPostByte processes the boundary. A remote request containing an exactly 256-byte multipart boundary wraps _boundaryPosition from 255 to zero, prevents the boundary parsing loop from terminating, consumes excessive CPU, and triggers a FreeRTOS watchdog reset on affected ESP32 or ESP8266 devices. This issue is fixed in version 3.11.1.

Database specific 
{
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
        "CWE-190"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/54xxx/CVE-2026-54571.json"
}
References

Affected packages

Git / github.com/esp32async/espasyncwebserver

Affected ranges

Type
GIT
Repo
https://github.com/esp32async/espasyncwebserver
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
b928de7cbd7debcd6266ece6a6c46f10a86d3a6f
Fixed
d6aa7daf0823a41966b1841826cff015237d6e42
Database specific
Show details 
{
    "extracted_events": [
        {
            "introduced": "0"
        },
        {
            "fixed": "3.11.1"
        }
    ],
    "source": [
        "AFFECTED_FIELD",
        "REFERENCES"
    ]
}

Affected versions

v3.*
v3.10.0
v3.10.1
v3.10.2
v3.10.3
v3.11.0
v3.6.0
v3.6.1
v3.6.2
v3.7.0
v3.7.1
v3.7.10
v3.7.2
v3.7.3
v3.7.4
v3.7.5
v3.7.6
v3.7.7
v3.7.8
v3.7.9
v3.8.0
v3.8.1
v3.9.0
v3.9.1
v3.9.2
v3.9.3
v3.9.4
v3.9.5
v3.9.6

Database specific

source 
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vanir_signatures_modified 
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