CVE-2026-55490
OpenWrt: EAD Integer Underflow → Pre-Auth Denial of Service
- State
- Published
- Severity
- 6.5 Medium
- Published
- Jul 7, 2026
- Updated
- Jul 8, 2026
- Reserved
- Jun 16, 2026
Description
OpenWrt is a Linux operating system targeting embedded devices. Before v25.12.5, an integer underflow in handle_send_a() of the Emergency Access Daemon allows any unauthenticated attacker on the local network to crash the daemon by sending a single crafted UDP packet. The message length underflows before a bounds check and is then passed to memcpy as a very large size. This issue is fixed v25.12.5.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 6.5 Medium | CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | GitHub_M |
Weaknesses
- CWE-191 Integer Underflow (Wrap or Wraparound)
Affected Products
| Product | Versions |
|---|---|
openwrtopenwrt |
|
References
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