CVE-2025-53007 arduino-esp32 vulnerable to CRLF injection in WebServer.cpp
Attackers can inject CRLF characters into HTTP headers via the sendHeader function, enabling HTTP response splitting and header manipulation in ESP32 applications.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2025-53007?
CVE-2025-53007 is a high-severity vulnerability in espressif arduino-esp32, published on 26 Jun 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
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.
Weakness: CWE-113
Which versions are affected by CVE-2025-53007?
How do I fix CVE-2025-53007?
No fix has been published for CVE-2025-53007 yet. Limit exposure of the affected software until one is available.
Is CVE-2025-53007 being exploited?
There is no known exploitation of CVE-2025-53007 in the wild and no public exploit code.
Sources
Also known as GHSA-5476-9jjq-563m.