CVE-2023-40019 | FreeSWITCH allows authorized users to cause a denial of service attack by sending re-INVITE with SDP containing duplicate codec names

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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 version 1.10.10, FreeSWITCH allows authorized users to cause a denial of service attack by sending re-INVITE with SDP containing duplicate codec names. When a call in FreeSWITCH completes codec negotiation, the `codec_string` channel variable is set with the result of the negotiation. On a subsequent re-negotiation, if an SDP is offered that contains codecs with the same names but with different formats, there may be too many codec matches detected by FreeSWITCH leading to overflows of its internal arrays. By abusing this vulnerability, an attacker is able to corrupt stack of FreeSWITCH leading to an undefined behavior of the system or simply crash it. Version 1.10.10 contains a patch for this issue.

Published: 2023-09-15 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2023-40019 is rated High Exploit Risk (60.7/100): CVSS High severity, with low exploitation likelihood (EPSS 0.23%). Core evidence: 1 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2023-40019

EDB-ID Source Kind Published Link
nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2023-40019

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2025-11-21 0.40% 0.23% -0.18%
2 2025-11-18 0.23% 0.40% +0.18%
3 2025-04-15 0.23%

Full EPSS history (8 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-40019

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
3.9 3.6 [email protected]
6.5 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
2.8 3.6 [email protected]

Weakness enumeration for CVE-2023-40019

OS Trackers for CVE-2023-40019

vendor priority summary link
alpine medium CVE-2023-40019: 1 source package rows (freeswitch); 5 state rows across 5 repos (3.19-main, 3.20-main, 3.21-main, 3.22-main, edge-main); fixed 0, open 5. https://security.alpinelinux.org/vuln/CVE-2023-40019

Affected software / configurations for CVE-2023-40019

Vendor Product Version Raw CPE
freeswitch freeswitch < 1.10.10 cpe:2.3:a:freeswitch:freeswitch:*:*:*:*:*:*:*:*

References for CVE-2023-40019

cvelogic Threat Intelligence