CVE-2026-42855 (GCVE-0-2026-42855)

Vulnerability from cvelistv5 – Published: 2026-05-12 21:56 – Updated: 2026-05-13 15:36
VLAI
Title
arduino-esp32: Digest authentication URI mismatch bypass in WebServer allows cross-resource replay attack
Summary
arduino-esp32 is an Arduino core for the ESP32, ESP32-S2, ESP32-S3, ESP32-C3, ESP32-C6 and ESP32-H2 microcontrollers. Prior to 3.3.8, the WebServer Digest authentication implementation in arduino-esp32 computes the authentication hash using the URI field from the client's Authorization header, without verifying that it matches the actual requested URI. This allows an attacker who possesses any valid digest response (computed for URI-A) to authenticate requests to a completely different protected URI (URI-B), bypassing per-resource access control. This vulnerability is fixed in 3.3.8.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-13 15:32 UTC
CWE
  • CWE-287 - Improper Authentication
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7809 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
espressif arduino-esp32 Affected: < 3.3.8
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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