CVE-2026-56786
Out-of-bounds write in RTKLIB decode_type1033 enables overflow from NTRIP/RTCM3 streams.
Is CVE-2026-56786 being exploited?
Not confirmed. CVE-2026-56786 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.71% probability of exploitation in the next 30 days.
How severe is CVE-2026-56786?
CVE-2026-56786 is rated Critical with a CVSS score of 9.3. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-56786?
Not known from our data. No patch reference has been recorded for CVE-2026-56786, which is not the same as no patch existing — a fix may have shipped without a tagged reference, or after this record was written. The vendor advisory is the only authority on whether a fix exists, and mitigations may be available regardless.
What does CVE-2026-56786 affect?
CVE-2026-56786 affects RTKLIB 2.4.3 and earlier. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-56786?
Plan upgrade to patched RTKLIB; review input streams.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Attacker-controlled RTCM3/NTRIP streams can overflow the 64-byte descriptor fields, risking arbitrary code execution or DoS.
Patch when possible
- affected<= 2.4.3
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.