VulnSocial

CVE-2026-45103General

LOWCVSS 7.5 · HIGH

Signal is active with 2 mentions in latest observed window

Immediate actions

  • Track advisory updates for patch or workaround availability

Recommended action window: Monitor and triage in normal cycle

NVD description

OpenSIPS is a Session Initiation Protocol (SIP) server implementation. In versions prior to 3.6.6 and 4.0.0-rc1, the TCP message framing layer parses the Content-Length header using unsigned int arithmetic with no overflow check. When an attacker sends a Content-Length value that overflows unsigned int (e.g., 4294967296), the framing layer computes a wrapped-around value (e.g., 0) and splits the TCP stream at the wrong boundary, causing the body of the first SIP message to be processed as a separate message and enabling SIP message smuggling. Because Content-Length is parsed in the transport layer before authentication, an unauthenticated, network-based attacker can smuggle arbitrary SIP messages over any TCP-based transport (proto_tcp, proto_tls, proto_ws, proto_wss) on any instance with TCP enabled, with no routing-script preconditions. This allows smuggled messages to bypass front-end SBC/proxy security policies, inherit the connection's authentication context, and evade rate limiting. This issue has been fixed in versions 3.6.6 and 4.0.0-rc1.

Back to dashboard
0.0/ 10 priority

Sources & remediation

Other references
Weakness type (CWE)
CWE-190

Priority

LOW

Exploitation

NONE

PoC

NONE

Patch

NONE

Momentum

NONE

Threat summary

  • 2 mentions across 1 observed day

What's happening

  • Technical details provided in 1 signal
  • General: 2 classified signals
  • 2 total mentions across 1 day

Deep dive

Activity timeline2 mentions / 1d
01122Mentions · 2026-08-05: 2Technical Details · 2026-08-05: 108-05
Signal classification1 categories
General
2100.0%
Referenced assets3 URLs
Full discourse2 posts
  • Vulmon Vulnerability Feed@VulmonFeeds
    General

    CVE-2026-45103 SIP Message Smuggling via Content-Length Integer Overflow in Open... https://vulmon.com/vulnerabilitydetails?qid=CVE-2026-45103 Customizable Vulnerability Alerts: https://alerts.vulmon.com/?utm_source=twitter&utm_medium=social&utm_campaign=2102281&utm_content=4

    Post summary

    The post references CVE-2026‑45103 as a SIP Content‑Length integer overflow leading to message smuggling, but offers no PoC, exploit details, active exploitation evidence, patch, or debunking claim.

    00000102
    4.1K followersView on X
  • CVE@CVEnew
    General

    CVE-2026-45103 OpenSIPS is a Session Initiation Protocol (SIP) server implementation. In versions prior to 3.6.6 and 4.0.0-rc1, the TCP message framing layer parses the Content-Leng… https://www.cve.org/CVERecord?id=CVE-2026-45103

    Post summary

    The text merely references a CVE record with a partial description and does not provide PoC, exploit, active exploitation, patch, or detailed vulnerability information.

    00000803
    57.9K followersView on X

Explore more

Back to dashboard