SignalWire FreeSwitch Code Injection
CVE-2026-116779 is a critical-severity improper neutralization of special elements used in a command vulnerability in freeswitch from Signalwire, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected freeswitch versions: < 1.11.3. The record does not name a fixed version, so check the vendor advisory. CISA added it to the Known Exploited Vulnerabilities catalogue on November 9, 2026, which means attacks have been observed in the wild.
Attackers are already exploiting this vulnerability, according to CISA.
What to do
- Check which version of freeswitch you run against the affected versions below, and install the vendor's latest release.
- CISA's required action: Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
- Read the advisory on github.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Signalwire | freeswitch | < 1.11.3 | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (github.com).
Official description
FreeSWITCH is a Software Defined Telecom Stack enabling the digital transformation from proprietary telecom switches to a software implementation that runs on any commodity hardware. Prior to 1.11.3, sofia_presence_handle_sip_i_message() split the To user of an inbound SIP MESSAGE on a plus sign and treated the left side as a chat protocol selector. Selecting the api chat proto reached switch_api_execute(), allowing a peer whose MESSAGE was accepted to run FreeSWITCH API commands, including operating-system command sinks, with the daemon's privileges. Inbound chat is enabled on the stock internal and external profiles, and any authenticated profile account is sufficient; stock directory users without password material can also remove that barrier in affected configurations. The flaw permits configuration and credential disclosure, arbitrary call control, and command execution, and exploitation has been observed in the wild. This issue is fixed in version 1.11.3.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Neutralization of Special Elements used in a Command
The product constructs all or part of a command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended command when it is sent to a downstream component.
How developers prevent this class of flaw
- If at all possible, use library calls rather than external processes to recreate the desired functionality.
- If possible, ensure that all external commands called from the program are statically created.
- Run time: Run time policy enforcement may be used in an allowlist fashion to prevent use of any non-sanctioned commands.
More Improper Neutralization of Special Elements used in a Command vulnerabilities (CWE-77)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: active, automatable: yes, technical impact: total).
- Added to CISA's Known Exploited Vulnerabilities catalogue.
- Record last changed materially (score, affected products, status or references).
- Deadline for US federal agencies to remediate, set by CISA.
References
Advisories
- github.com/signalwire/freeswitch/security/advisories/GHSA-mg63-h38w-8p9pMitigation, Third Party Advisory
Patches and release notes
Third-party and government advisories
- cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-116779US Government Resource
Our coverage
Other vulnerabilities in freeswitch
- 9.1 Critical severity
- 7.4 High severity
- 8.2 High severity
- 7.5 High severity
- 8.8 High severity
- 9.1 Critical severity
Recent Improper Neutralization of Special Elements used in a Command vulnerabilities
- 8.8 High severity
- 7.3 High severity
- 9.9 Critical severity
- 10.0 Critical severity
- 9.1 Critical severity
- 9.1 Critical severity
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