Bug 2493113 (CVE-2026-56786)

Summary: CVE-2026-56786 rtklib: RTKLIB 2.4.3 - Out-of-bounds Write in decode_type1033 via Crafted RTCM3 Message
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: urgent Docs Contact:
Priority: urgent    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 2494496, 2494499    
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Description OSIDB Bzimport 2026-06-25 19:02:42 UTC 
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.