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TI-2026-85604 Aliases CVE-2026-116574

Off-by-one heap write in FreeSWITCH XML serialization

Priority LOW 27CWE-193Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
High
Impact type
—
Confidentiality · integrity · availability
None · Low · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA.

Summary

FreeSWITCH before 1.11.2 has an off-by-one heap write in XML serialization, where switch_xml_ampencode() reserves too little space for a four-byte UTF-8 character reference (CWE-193). A remote attacker with low privileges can trigger it by supplying text that is serialized at a buffer boundary. The NUL terminator writes one byte past the allocation, which can abort the process or truncate an adjacent object, and remote code execution has not been demonstrated.

Written with Claude Haiku 5.5 from the sources below · 2026-11-05

Description from the CNA

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 1.11.2, switch_xml_ampencode() reserved only ten bytes for the widest numeric character reference produced from a four-byte UTF-8 sequence, omitting space for the terminating NUL. When remote-supplied text was serialized at the exact buffer-growth boundary, the terminator wrote one byte beyond the heap allocation. Reachable surfaces include mod_xml_cdr, conference and formatted CDR XML, XML Event Socket output, and XML API output that serializes caller-controlled values. The fixed zero-byte write can abort the process or truncate an adjacent object, while remote code execution has not been demonstrated. This issue is fixed in version 1.11.2.

Why it matters now

EPSS 0.00379 32nd percentileScored 2026-11-07
Fix Fixed freeswitch (signalwire): 1.11.2

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
signalwirefreeswitchbefore 1.11.21.11.2Patch availableCNA
  • freeswitch Vendorsignalwire Affected before 1.11.2 Fixed in 1.11.2 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:freeswitch:freeswitch:*:*:*:*:*:*:*:*——freeswitch
  • cpe:2.3:a:freeswitch:freeswitch:*:*:*:*:*:*:*:* Versions — — ·freeswitch

Remediation

Upgrade FreeSWITCH to version 1.11.2, which fixes this issue.

Written with Claude Haiku 5.5 from the sources below · 2026-11-05

  • Fix · CNA freeswitch (signalwire) Fixed in 1.11.2

Timeline

  1. 2026-11-05 Threatist record created from CVE-2026-116574
  2. 2026-11-07 Priority changed: MEDIUM → LOW

References

Other 3

  • TI-2023-08915 heap-over-flow in stun_parse_attribute in sofia-sip CVSS 3.1CRITICAL 9.8
  • TI-2022-13049 Heap-based Buffer Overflow and Out-of-bounds Write in Sofia-SIP CVSS 3.1CRITICAL 9.8
  • TI-2023-28097 FreeSWITCH susceptible to Denial of Service via DTLS Hello packets during call initiation CVSS 3.1HIGH 7.5
  • TI-2023-20909 Resource allocation without limits in signalwire freeswitch CVSS 3.1HIGH 7.5
  • TI-2023-20908 FreeSWITCH allows remote users to trigger out of bounds write by offering an ICE candidate with unknown component ID CVSS 3.1HIGH 7.5
  • TI-2023-15601 heap-over-flow and integer-overflow in sofia-sip CVSS 3.1HIGH 7.5
See all 44 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences