Bug 2528784 (CVE-2026-57161)

Summary: CVE-2026-57161 pjsip: stack overflow handling Service-Route headers in a registration response
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
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Priority: high    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in PJSIP. A stack buffer overflow exists in PJSUA when processing Service-Route headers in a registration response. A malicious registrar that returns an excessive number of Service-Route headers can exploit this to write past the end of the array on the stack. This can result in an unexpected application termination, leading to a Denial of Service (DoS). This vulnerability affects applications that register using the PJSUA/PJSUA2 account API (the default registration path).
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 2531082, 2531083, 2531084, 2531085    
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Description OSIDB Bzimport 2026-09-04 17:33:11 UTC 
PJSIP is a free and open source multimedia communication library written in C. Prior to commit acc03b5, a stack buffer overflow exists in PJSUA when processing Service-Route headers in a registration response (update_service_route() in pjsua_acc.c). This affects applications that register using the PJSUA/PJSUA2 account API (the default registration path). The Service-Route URIs from a 2xx response to REGISTER are stored into a fixed-size array without bounding the number of headers; a registrar that returns an excessive number of Service-Route headers can write past the end of the array on the stack. The values written are internal pointers rather than arbitrary data, so the most likely impact is unexpected application termination (denial of service), though memory corruption cannot be excluded. The malicious response may come from a compromised or malicious registrar, or — over unprotected transports — a spoofed response. This issue has been patched via commit acc03b5.