CVE-2026-5067Disclosure(zephyrproject / zephyr)

LOWCVSS 9.8 · CRITICAL

Signal is active with 1 mentions in latest observed window

Immediate actions

  • Patch zephyrproject zephyr systems immediately

Recommended action window: Monitor and triage in normal cycle

NVD description

A remote, unauthenticated attacker can trigger memory corruption in Zephyr's HTTP server WebSocket upgrade path by sending a crafted Sec-WebSocket-Key header. The HTTP/1 header parser copies the header into a fixed-size buffer using a bounded copy that does not guarantee NUL termination when the input length reaches the buffer size. During upgrade handling the buffer is copied to a local stack buffer and passed to strlen(); if no NUL exists in-bounds, strlen() reads beyond the stack buffer and subsequent concatenation with the WebSocket magic string can write out of bounds. This leads to out-of-bounds read and write on stack memory, resulting in crash (denial of service) and potentially code execution. The path is reachable when CONFIG_HTTP_SERVER_WEBSOCKET is enabled.

0.5/ 10 priority

Sources & remediation

Weakness type (CWE)
CWE-170CWE-787

Priority

LOW

Exploitation

NONE

PoC

YES

Patch

AVAILABLE

Momentum

NONE

Are you affected?

If you run products in this scope, you should treat this CVE as relevant to your environment.

  • zephyr

Threat summary

  • Patch or workaround signal is available
  • 1 mentions across 1 observed day

What's happening

  • Patch or workaround mentioned in 1 signal
  • Technical details provided in 1 signal
  • Disclosure: 1 classified signal
  • 1 total mentions across 1 day

Affected systems

Products
zephyr

Deep dive

Activity timeline1 mentions / 1d
00111Mentions · 2026-06-15: 1Patch / Workaround · 2026-06-15: 1Technical Details · 2026-06-15: 106-15
Signal classification1 categories
Disclosure
1100.0%
Referenced assets1 URL
By indicator
Full discourse1 post
  • SecAlerts@SecAlertsCo
    Disclosure

    🔌 CVE-2026-5067: Critical (9.8) unauthenticated memory corruption in Zephyr's HTTP WebSocket upgrade path. A crafted Sec-WebSocket-Key triggers out-of-bounds read/write. No auth, no interaction needed. Patch if you're running Zephyr RTOS. https://secalerts.co/vulnerability/CVE-2026-5067 https://t.co/Fe3HNRKwjm

    Post summary

    A critical unauthenticated memory corruption vulnerability (CVE‑2026‑5067) in Zephyr’s HTTP WebSocket upgrade path allows an attacker to trigger out‑of‑bounds read/write via a crafted Sec‑WebSocket‑Key; a patch is available.

    0000074
    835 followersView on X
CPE platform detail1 entries

1 of 1 entries

PartVendorProductVersionTarget SWTarget HW
OSzephyrprojectzephyr---

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