CVE-2026-90780 SIPp CVE debrief

Who should care

Defenders responsible for SIPp installations, network administrators, and security teams should assess exposure and prioritize verification and remediation efforts. They should review and apply patches or updates for SIPp, monitor for suspicious SIP message activity, and verify the integrity of SIPp installations. Additionally, they should assess the feasibility of remote, unauthenticated attacks and review compensating controls for exposed systems.

Why it matters

CVE-2026-90780 is a buffer overflow vulnerability in SIPp through 3.7.7 that can be exploited by unauthenticated remote attackers to crash the process. Defenders should prioritize verifying exposure, applying patches, and monitoring for suspicious activity.

• Potential for remote, unauthenticated denial-of-service (DoS) attacks
• Need for verification of SIPp installations and exposure
• Priority for applying patches or updates to prevent exploitation
• Potential for increased monitoring and logging to detect suspicious SIP message activity

Technical summary

The get_header() function in src/sip_parser.cpp of SIPp through 3.7.7 is vulnerable to a buffer overflow when processing SIP messages with header content exceeding 20,490 bytes. Unauthenticated remote attackers can send crafted SIP messages with oversized headers to overflow the static buffer and crash the process. This vulnerability can be exploited to cause a denial-of-service (DoS) attack. Defenders should prioritize verifying exposure of SIPp installations to this buffer overflow vulnerability and assess the feasibility of remote, unauthenticated attacks.

Defensive priority

Defenders should prioritize verifying exposure of SIPp installations to this buffer overflow vulnerability and assess the feasibility of remote, unauthenticated attacks.

Recommended defensive actions

• Verify SIPp installations for exposure to this buffer overflow vulnerability
• Assess network exposure and feasibility of remote, unauthenticated attacks
• Review and apply patches or updates for SIPp
• Monitor for suspicious SIP message activity
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented

Evidence notes

The CVE record and NVD entry provide details on the buffer overflow vulnerability in SIPp through 3.7.7. The get_header() function in src/sip_parser.cpp is vulnerable when processing SIP messages with header content exceeding 20,490 bytes.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.