CVE-2026-56786 | RTKLIB through 2.4.3 contains an out-of-bounds write vulnera… | CVSS 9.8 CRITICAL

Description

RTKLIB through 2.4.3 contains an out-of-bounds write vulnerability in decode_type1033 function that fails to clamp length counters to destination buffer size, allowing up to 191-byte overflow into fixed 64-byte descriptor fields. An attacker controlling an NTRIP or serial RTCM3 correction stream can craft a valid CRC-bearing type-1033 message to corrupt adjacent rtcm_t object members, potentially achieving arbitrary code execution or denial of service.

Metadata

CVE ID: CVE-2026-56786
State: PUBLISHED
Assigner: VulnCheck
Reserved: 2026-06-23 01:24 UTC
Published: 2026-06-25 18:11 UTC
Last updated: 2026-06-25 18:41 UTC
Primary CWE: CWE-787
Out-of-bounds Write
Vendor / Product: tomojitakasu / RTKLIB
Sources: cve.org · NVD

Severity & Metrics

9.8 CRITICAL CVSS 3.1

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

SSVC — CISA Coordinator

Exploitation: PoC
Automatable: yes
Tech. Impact: total

Affected products (1)

Vendor	Product	Platform	Versions
tomojitakasu	RTKLIB	—	0 ≤ 2.4.3

Weakness (CWE)

CWE	Source	Description
CWE-787	cna	Out-of-bounds Write

CVSS scores (2)

Score	Severity	Version	Source	Vector
9.8	CRITICAL	3.1	cna	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
9.3	CRITICAL	4.0	cna	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

References (2)