ubuntu-cve-2026-45538
Vulnerability from osv_ubuntu
OpenSIPS is a Session Initiation Protocol (SIP) server implementation. In versions 4.0.0 and prior, processing a SIP message with a header name longer than 255 bytes causes a stack buffer overflow when sip_to_json() is called in the routing script. Function sip_to_json() (modules/sipmsgops/sipmsgops.c) copies SIP header names into a fixed 255-byte stack buffer without bounds checking, performing a memcpy of the full header-name length even though the SIP parser imposes no such limit (a header name can be roughly 65000 bytes). As a result, when a routing script calls sip_to_json(), a SIP message with a header name longer than 255 bytes triggers a stack buffer overflow in which both the length and content of the overwrite are attacker-controlled, corrupting the saved frame pointer and return address. A single unauthenticated UDP packet to the SIP port (5060) can crash the process or, on builds without stack protections, hijack the return address to achieve remote code execution. This affects deployments whose routing script invokes sip_to_json(). This issue was not fixed at the time of publication.
{
"affected": [
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "opensips",
"binary_version": "2.2.2-3build4"
},
{
"binary_name": "opensips-b2bua-module",
"binary_version": "2.2.2-3build4"
},
{
"binary_name": "opensips-berkeley-bin",
"binary_version": "2.2.2-3build4"
},
{
"binary_name": "opensips-berkeley-module",
"binary_version": "2.2.2-3build4"
},
{
"binary_name": "opensips-carrierroute-module",
"binary_version": "2.2.2-3build4"
},
{
"binary_name": "opensips-compression-module",
"binary_version": "2.2.2-3build4"
},
{
"binary_name": "opensips-console",
"binary_version": "2.2.2-3build4"
},
{
"binary_name": "opensips-cpl-module",
"binary_version": "2.2.2-3build4"
},
{
"binary_name": "opensips-dbhttp-module",
"binary_version": "2.2.2-3build4"
},
{
"binary_name": "opensips-dialplan-module",
"binary_version": "2.2.2-3build4"
},
{
"binary_name": "opensips-emergency-module",
"binary_version": "2.2.2-3build4"
},
{
"binary_name": "opensips-geoip-module",
"binary_version": "2.2.2-3build4"
},
{
"binary_name": "opensips-http-modules",
"binary_version": "2.2.2-3build4"
},
{
"binary_name": "opensips-identity-module",
"binary_version": "2.2.2-3build4"
},
{
"binary_name": "opensips-jabber-module",
"binary_version": "2.2.2-3build4"
},
{
"binary_name": "opensips-json-module",
"binary_version": "2.2.2-3build4"
},
{
"binary_name": "opensips-ldap-modules",
"binary_version": "2.2.2-3build4"
},
{
"binary_name": "opensips-lua-module",
"binary_version": "2.2.2-3build4"
},
{
"binary_name": "opensips-memcached-module",
"binary_version": "2.2.2-3build4"
},
{
"binary_name": "opensips-mysql-module",
"binary_version": "2.2.2-3build4"
},
{
"binary_name": "opensips-perl-modules",
"binary_version": "2.2.2-3build4"
},
{
"binary_name": "opensips-postgres-module",
"binary_version": "2.2.2-3build4"
},
{
"binary_name": "opensips-presence-modules",
"binary_version": "2.2.2-3build4"
},
{
"binary_name": "opensips-rabbitmq-module",
"binary_version": "2.2.2-3build4"
},
{
"binary_name": "opensips-radius-modules",
"binary_version": "2.2.2-3build4"
},
{
"binary_name": "opensips-redis-module",
"binary_version": "2.2.2-3build4"
},
{
"binary_name": "opensips-regex-module",
"binary_version": "2.2.2-3build4"
},
{
"binary_name": "opensips-restclient-module",
"binary_version": "2.2.2-3build4"
},
{
"binary_name": "opensips-sctp-module",
"binary_version": "2.2.2-3build4"
},
{
"binary_name": "opensips-snmpstats-module",
"binary_version": "2.2.2-3build4"
},
{
"binary_name": "opensips-sqlite-module",
"binary_version": "2.2.2-3build4"
},
{
"binary_name": "opensips-tls-module",
"binary_version": "2.2.2-3build4"
},
{
"binary_name": "opensips-tlsmgm-module",
"binary_version": "2.2.2-3build4"
},
{
"binary_name": "opensips-unixodbc-module",
"binary_version": "2.2.2-3build4"
},
{
"binary_name": "opensips-wss-module",
"binary_version": "2.2.2-3build4"
},
{
"binary_name": "opensips-xmlrpc-module",
"binary_version": "2.2.2-3build4"
},
{
"binary_name": "opensips-xmpp-module",
"binary_version": "2.2.2-3build4"
}
]
},
"package": {
"ecosystem": "Ubuntu:18.04:LTS",
"name": "opensips",
"purl": "pkg:deb/ubuntu/opensips@2.2.2-3build4?arch=source\u0026distro=bionic"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"2.2.2-3build2",
"2.2.2-3build3",
"2.2.2-3build4"
]
}
],
"aliases": [],
"details": "OpenSIPS is a Session Initiation Protocol (SIP) server implementation. In versions 4.0.0 and prior, processing a SIP message with a header name longer than 255 bytes causes a stack buffer overflow when sip_to_json() is called in the routing script. Function sip_to_json() (modules/sipmsgops/sipmsgops.c) copies SIP header names into a fixed 255-byte stack buffer without bounds checking, performing a memcpy of the full header-name length even though the SIP parser imposes no such limit (a header name can be roughly 65000 bytes). As a result, when a routing script calls sip_to_json(), a SIP message with a header name longer than 255 bytes triggers a stack buffer overflow in which both the length and content of the overwrite are attacker-controlled, corrupting the saved frame pointer and return address. A single unauthenticated UDP packet to the SIP port (5060) can crash the process or, on builds without stack protections, hijack the return address to achieve remote code execution. This affects deployments whose routing script invokes sip_to_json(). This issue was not fixed at the time of publication.",
"id": "UBUNTU-CVE-2026-45538",
"modified": "2026-08-04T21:16:00Z",
"published": "2026-08-04T21:16:00Z",
"references": [
{
"type": "REPORT",
"url": "https://ubuntu.com/security/CVE-2026-45538"
},
{
"type": "REPORT",
"url": "https://www.cve.org/CVERecord?id=CVE-2026-45538"
},
{
"type": "REPORT",
"url": "https://github.com/OpenSIPS/opensips/security/advisories/GHSA-37wc-5j8j-95x3"
}
],
"related": [],
"schema_version": "1.7.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
},
{
"score": "medium",
"type": "Ubuntu"
}
],
"upstream": [
"CVE-2026-45538"
]
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.