CVE-2025-34468

Publication date 31 December 2025

Last updated 10 July 2026

Ubuntu priority

Medium

Why this priority?

Cvss 3 Severity Score

9.8 · Critical

Score breakdown

Description

libcoap versions up to and including 4.3.5, prior to commit 30db3ea, contain a stack-based buffer overflow in address resolution when attacker-controlled hostname data is copied into a fixed 256-byte stack buffer without proper bounds checking. A remote attacker can trigger a crash and potentially achieve remote code execution depending on compiler options and runtime memory protections. Exploitation requires the proxy logic to be enabled (i.e., the proxy request handling code path in an application using libcoap).

Status

Package Ubuntu Release Status
libcoap3 26.04 LTS resolute
Needs evaluation
25.10 questing Ignored end of life, was needs-triage
25.04 plucky Ignored end of life, was needs-triage
24.04 LTS noble
Needs evaluation
22.04 LTS jammy
Needs evaluation
libcoap 26.04 LTS resolute Not in release
25.10 questing Not in release
25.04 plucky Not in release
24.04 LTS noble Not in release
22.04 LTS jammy Not in release
18.04 LTS bionic
Needs evaluation
libcoap2 26.04 LTS resolute Not in release
25.10 questing Not in release
25.04 plucky Not in release
24.04 LTS noble Not in release
22.04 LTS jammy
Needs evaluation
20.04 LTS focal
Needs evaluation

Severity score breakdown

CVSS version:

Base score 8.2 · High

Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Base score 9.8 · Critical

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References

Other references

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