CVE-2026-90780

SIPp through 3.7.7 Buffer Overflow via Oversized SIP Header Content

Published Sep 13, 2026 CVSS 4.0 · 8.7 High EPSS < 1% KEV · Not listed

Description

SIPp through 3.7.7 contains a buffer overflow vulnerability in the get_header() function in src/sip_parser.cpp 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.

Analysis

Technical impact

SIPp versions up to 3.7.7 contain a buffer overflow in the get_header() routine of src/sip_parser.cpp when a SIP message contains header content larger than 20,490 bytes. The overflow corrupts a static buffer, causing the SIPp process to crash. Attackers do not need authentication and can trigger the vulnerability remotely by sending a crafted SIP message with an oversized header, leading to disruption of the application's availability.

Affected Systems

The vulnerable product is SIPp, specifically releases 3.7.7 and earlier. All installations of these versions that receive unfiltered SIP traffic are at risk.

Risk and Exploitability

The CVSS score of 8.7 signals a high‑severity flaw. The EPSS score is < 1%, indicating a very low exploitation probability, and the vulnerability is not yet listed in CISA’s KEV catalog, suggesting the public is still becoming aware of it. An unauthenticated attacker can exploit this by injecting a malicious SIP request with an excessively large header; successful exploitation results in a process crash, making the application unavailable until it is restarted. The exposure is remote and does not require local or privileged access.

Affected Products

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

SIPp

sipp

unaffected

Version	Status	Constraints
`0`	affected	≤ 3.7.7

No data.

Vendor Product Versions

Sipp

Version	Status	Scheme	Platform
`[0,3.7.7]`	affected	semver	—

Remediation

No solution or workaround provided in the CVE record.

OpenCVE Recommended Actions

Upgrade SIPp to version 3.7.8 or later to apply the buffer overflow fix.
If an upgrade is not possible, apply the source patch corresponding to commit 8ddfb43359703e665041a955543e07f504f80232 or merge pull request 881 to correct the header parsing loop.
As a temporary mitigation, configure your network or SIP proxy to reject or truncate SIP messages whose headers exceed 20,490 bytes, preventing the overflow from reaching the application.

Generated by OpenCVE AI on September 15, 2026 at 16:53 UTC.

Tracking

Advisories

No advisories available

Metrics

Attack Vector Network

Attack Complexity Low

Privileges Required None

Attack Requirements None

User Interaction None

Vulnerable System Confidentiality Impact None

Vulnerable System Integrity Impact None

Vulnerable System Availability Impact High

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploit prediction score: < 1% (0.857% probability within 30 days)

Exploitation none

Automatable yes

Technical Impact partial

References

Link	Providers
https://github.com/SIPp/sipp
https://github.com/SIPp/sipp/blob/v3.7.7/src/sip_parser.cpp#L164-L227
https://github.com/SIPp/sipp/commit/8ddfb43359703e665041a955543e07f504f80232
https://github.com/SIPp/sipp/pull/881
https://www.vulncheck.com/advisories/sipp-through-3.7.7-buffer-overflow-via-oversized-sip-header-content

History

Sep 20, 2026 1:30 AM Scoring metrics updated View changes

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Sep 14, 2026 1:15 AM First appearance in the feed. Affected vendors updated View changes

Type	Values Removed	Values Added
First Time appeared		Sipp Sipp sipp
Vendors & Products		Sipp Sipp sipp

Sep 13, 2026 11:45 AM Description updated. Title updated. Weaknesses updated. Added references. Scoring metrics updated View changes

Type	Values Removed	Values Added
Description		SIPp through 3.7.7 contains a buffer overflow vulnerability in the get_header() function in src/sip_parser.cpp 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.
Title		SIPp through 3.7.7 Buffer Overflow via Oversized SIP Header Content
Weaknesses		CWE-120
References		https://github.com/SIPp/sipp https://github.com/SIPp/sipp/blob/v3.7.7/src/sip_parser.cpp#L164-L227 https://github.com/SIPp/sipp/commit/8ddfb43359703e665041a955543e07f504f80232 https://github.com/SIPp/sipp/pull/881 https://www.vulncheck.com/advisories/sipp-through-3.7.7-buffer-overflow-via-oversized-sip-header-content
Metrics		cvssV3_1 `{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}` cvssV4_0 `{'score': 8.7, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N'}`