CVE-2026-55490
OpenWrt: EAD Integer Underflow → Pre-Auth Denial of Service
CVSS Score
6.5
EPSS Score
0.6%
EPSS Percentile
47th
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.
| CWE | CWE-191 |
| Vendor | openwrt |
| Product | openwrt |
| Published | Jul 7, 2026 |
| Last Updated | Jul 8, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Attack Vector
Adjacent
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Affected Versions
openwrt / openwrt
< 25.12.5