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TI-2025-33011 Aliases CVE-2025-53007

arduino-esp32 vulnerable to CRLF injection in WebServer.cpp

Priority MEDIUM 45CWE-113Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
—
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0047 40th percentileScored 2026-11-07
Fix Fixed arduino-esp32 (espressif): 3.2.1, 3.3.0-RC1

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
espressifarduino-esp32before 3.2.1; 3.3.0-alpha1 to before 3.3.0-RC13.2.1, 3.3.0-RC1Patch availableCNA
  • arduino-esp32 Vendorespressif Affected before 3.2.1; 3.3.0-alpha1 to before 3.3.0-RC1 Fixed in 3.2.1, 3.3.0-RC1 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:espressif:arduino-esp32:*:*:*:*:*:*:*:*——espressif
  • cpe:2.3:a:espressif:arduino-esp32:*:*:*:*:*:*:*:* Versions — — ·espressif

Remediation

  • Fix · CNA arduino-esp32 (espressif) Fixed in 3.2.1, 3.3.0-RC1

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-53007

References

Other 4

  • TI-2026-31061 arduino-esp32: Stack buffer overflow in WebServer multipart boundary parsing leads to remote crash potential RCE CVSS 3.1CRITICAL 9.8
  • TI-2024-30765 Multiple Poisoned Pipeline Execution (PPE) vulnerabilities CVSS 3.1CRITICAL 10.0
  • TI-2026-30028 Improper validation of NBNS name_len in arduino-esp32 NetBIOS leads to memory corruption CVSS 3.1HIGH 8.8
  • TI-2025-33484 CSRF Vulnerability in Firmware Update Endpoints Allows Remote Code Execution CVSS 4.0HIGH 8.7
  • TI-2024-22076 Buffer Overflow vulnerability in esp-idf v.5.1 allows a remote attacker to execute… CVSS 3.1MEDIUM 6.5
  • TI-2026-85138 Unvalidated stack pointer at ESP-TEE boundary in esp-idf CVSS 3.1CRITICAL 9.3
See all 58 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences