Vulnerability · Published Jun 25, 2026 · Assigned by VulnCheck
CVE-2026-56786RTKLIB 2.4.3 - Out-of-bounds Write in decode_type1033 via Crafted RTCM3 Message
Critical 9.8
In plain English
A critical-severity out-of-bounds write in RTKLIB from tomojitakasu. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.7% (higher than 54% of all known vulnerabilities).
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | rtklib | no fix listed | DEBIAN-CVE-2026-56786 |
| Debian:13 | rtklib | no fix listed | DEBIAN-CVE-2026-56786 |
| Debian:14 | rtklib | no fix listed | DEBIAN-CVE-2026-56786 |
| Ubuntu:22.04:LTS | rtklib | no fix listed | UBUNTU-CVE-2026-56786 |
| Ubuntu:24.04:LTS | rtklib | no fix listed | UBUNTU-CVE-2026-56786 |
| Ubuntu:25.10 | rtklib | no fix listed | UBUNTU-CVE-2026-56786 |
| Ubuntu:26.04:LTS | rtklib | no fix listed | UBUNTU-CVE-2026-56786 |
| Ubuntu:26.10 | rtklib | no fix listed | UBUNTU-CVE-2026-56786 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| tomojitakasu | RTKLIB | 0 – through 2.4.3 |
Weakness: CWE-787 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
References
- Researcher Disclosure technical-description, exploit
- https://www.vulncheck.com/advisories/rtklib-out-of-bounds-write-in-decode-type1033-via-crafted-rtcm3-message third-party-advisory