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3 vulnerabilities found for ESPAsyncWebServer by ESP32Async
CVE-2026-62966 (GCVE-0-2026-62966)
Vulnerability from cvelistv5
Published
2026-10-30 20:53
Modified
2026-10-30 20:53
Severity ?
VLAI Severity ?
EPSS score ?
CWE
Summary
ESPAsyncWebServer is an asynchronous HTTP and WebSocket server library for ESP32, ESP8266, RP2040 and RP2350. Prior to version 3.11.2, the multipart parser in `src/WebRequest.cpp` frees `_itemBuffer` and sets it to NULL when `BOUNDARY_OR_DATA` matches the closing boundary of a file part, before confirming the following terminator, while leaving `_itemIsFile` true. If the next byte is neither the final closing dashes nor a clean CRLF, the `DASH3_OR_RETURN2` or `EXPECT_FEED2` rewind branch re-injects provisionally consumed bytes through `itemWriteByte`. Because `_itemIsFile` remains true, `_itemBuffer`[`_itemBufferIndex`++] writes through a null pointer. On ESP32 this causes a `StoreProhibited` exception, panic and device reboot, producing remote denial of service. A route with a non-trivial body/upload handler, such as a file-upload or web-OTA endpoint, must be present. This issue is fixed in version 3.11.2.
References
| URL | Tags | |
|---|---|---|
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| ESP32Async | ESPAsyncWebServer |
Version: < 3.11.2 |
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}
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CVE-2026-54571 (GCVE-0-2026-54571)
Vulnerability from cvelistv5
Published
2026-09-17 18:28
Modified
2026-09-21 21:05
Severity ?
VLAI Severity ?
EPSS score ?
CWE
- CWE-190 - Integer Overflow or Wraparound
Summary
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.
References
| URL | Tags | |
|---|---|---|
|
|
||
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| ESP32Async | ESPAsyncWebServer |
Version: < 3.11.1 |
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CVE-2025-53094 (GCVE-0-2025-53094)
Vulnerability from cvelistv5
Published
2025-06-27 19:57
Modified
2025-06-27 20:19
Severity ?
VLAI Severity ?
EPSS score ?
CWE
Summary
ESPAsyncWebServer is an asynchronous HTTP and WebSocket server library for ESP32, ESP8266, RP2040 and RP2350. In versions up to and including 3.7.8, a CRLF (Carriage Return Line Feed) injection vulnerability exists in the construction and output of HTTP headers within `AsyncWebHeader.cpp`. Unsanitized input allows attackers to inject CR (`\r`) or LF (`\n`) characters into header names or values, leading to arbitrary header or response manipulation. Manipulation of HTTP headers and responses can enable a wide range of attacks, making the severity of this vulnerability high. A fix is available at pull request 211 and is expected to be part of version 3.7.9.
References
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| ESP32Async | ESPAsyncWebServer |
Version: <= 3.7.8 |
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