Vulnerability · Published Jul 2, 2026 · Assigned by VulnCheck

CVE-2026-58465Eclipse Wakaama CoAP Block1 Handler Unbounded Memory Allocation DoS

High 7.5

In plain English

A high-severity resource allocation without limits in wakaama from eclipse-wakaama. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.9% (higher than 61% of all known vulnerabilities).

Severity (CVSS 3.1)7.5High

Exploit odds (30 days)0.9%top 39.5% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

Eclipse Wakaama before snapshot/2026-05-26 contains an unbounded memory allocation vulnerability in the CoAP Block1 handler within coap/block.c that allows unauthenticated remote attackers to exhaust server memory by sending a sequence of Block1 PUT requests with incrementing block numbers. Attackers can target the registration endpoint over UDP without authentication, causing the server to repeatedly reallocate a growing accumulation buffer by appending each block payload without enforcing any maximum total size limit, resulting in denial of service through memory exhaustion.

Affected products (as reported)

Vendor	Product	Versions
eclipse-wakaama	wakaama	0 – before snapshot/2026-05-26

Weakness: CWE-770 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References

Release Notes release-notes
Fix PR issue-tracking
Fix Patch patch
https://www.vulncheck.com/advisories/eclipse-wakaama-coap-block1-handler-unbounded-memory-allocation-dos third-party-advisory