CVE-2026-46334Public exploitNetwork attack vector

Worker crash via malformed SDP bandwidth cloning

Published Aug 4, 2026 · Updated Aug 5, 2026

Denial of service in OpenSIPS 3.4.0 through 3.6.5 and 4.0.0-beta allows remote attackers to crash a worker via malformed SDP. extract_bwidth() performs pointer arithmetic on a null delimiter result, leaving oversized bw_type and bw_width lengths that clone_sdp_session_cell() passes to memcpy(). Unauthenticated reachability requires a routing script that parses attacker-controlled SDP and then clones it through dialog and QoS processing, causing a worker crash.

CVSS severity8.7
High
EPSS probability0.49%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Denial of service in OpenSIPS 3.4.0 through 3.6.5 and 4.0.0-beta allows remote attackers to crash a worker via malformed SDP. extract_bwidth() performs pointer arithmetic on a null delimiter result, leaving oversized bw_type and bw_width lengths that clone_sdp_session_cell() passes to memcpy(). Unauthenticated reachability requires a routing script that parses attacker-controlled SDP and then clones it through dialog and QoS processing, causing a worker crash.

The record

CVE
CVE-2026-46334
Published
Aug 4, 2026
Updated
Aug 5, 2026
Vendor
OpenSIPS
Product
OpenSIPS
Classifications
CWE-20, CWE-476, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 4, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 5, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=>= 3.4.0, < 3.6.6
  2. Affected versionversion=>= 4.0.0-beta, < 4.0.0-rc1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

OpenSIPS · OpenSIPSversion=>= 3.4.0, < 3.6.6; version=>= 4.0.0-beta, < 4.0.0-rc1

Published CVSS scores

8.7GitHubCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-20Improper Input Validation
CWE-476NULL Pointer Dereference
T1499.004Application or System Exploitation Flood

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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