CVE-2025-53007

published 2025-06-26

CVE-2025-53007: arduino-esp32 provides an Arduino core for the ESP32. Versions prior to 3.3.0-RC1 and 3.2.1 contain a HTTP Response Splitting vulnerability. The `sendHeader`…

Priority P3 53 high 8.9 CVSS 4.0

AV N AC L AT N PR N UI N VC H VI H VA H SC N SI N SA N E P CR X IR X AR X MAV X MAC X MAT X MPR X MUI X MVC X MVI X MVA X MSC X MSI X MSA X S X AU X R X V X RE X U X

arduino-esp32 provides an Arduino core for the ESP32. Versions prior to 3.3.0-RC1 and 3.2.1 contain a HTTP Response Splitting vulnerability. The `sendHeader` function takes arbitrary input for the HTTP header name and value, concatenates them into an HTTP header line, and appends this to the outgoing HTTP response headers. There is no validation or sanitization of the `name` or `value` parameters before they are included in the HTTP response. If an attacker can control the input to `sendHeader` (either directly or indirectly), they could inject carriage return (`\r`) or line feed (`\n`) characters into either the header name or value. This could allow the attacker to inject additional headers, manipulate the structure of the HTTP response, potentially inject an entire new HTTP response (HTTP Response Splitting), and/or ause header confusion or other HTTP protocol attacks. Versions 3.3.0-RC1 and 3.2.1 contain a fix for the issue.

Affected

2 ranges

Vendor	Product	Version range	Fixed in
espressif	arduino-esp32	< 3.2.1	3.2.1
espressif	arduino-esp32	—	—

Stop checking back — get the weekly exploitation signal.

Every Monday: what got weaponized or added to CISA KEV in the last seven days — each CVE cross-linked to its PoC, Nuclei template, and detection rule. Free, one email a week, unsubscribe in one click.

CWE-113