Signalwire vulnerabilities, page 2
45 vulnerabilities
Known vulnerabilities in Signalwire products, newest first, with CVSS severity, EPSS, KEV listings and ransomware use, across 3 products.
RoutineCVE-2026-116573signalwire · freeswitchFreeSWITCH mod_sofia: stack buffer overflow from an over-long SIP To-header userFreeSWITCH is an open-source software telecommunications platform. From 1.10.0 until 1.11.1, a stack-based buffer overflow in mod_sofia when generating dialog-event notifications. A peer can establish a dialog with an excessively long SIP To-header user part and subsequently subscribe to that entity’s dialog events, causing the stored value to overflow a fixed-size stack buffer. Exploitation requires presence or shared-appearance management to be enabled and normally requires valid profile credentials, unless subscription authentication is disabled. The overflow can terminate the FreeSWITCH process and all active calls. This vulnerability is fixed in version 1.11.2.CVSS6.5MediumEPSS0.46%PrioritiseCVE-2026-49846signalwire · libkslibks has path traversal in kws HTTP parser via URI segment overflowlibks provides foundational support for signalwire C products. Prior to version 2.0.11, `clean_uri()` in libks's HTTP request parser fails to reject URIs whose path has more segments than its internal canonicalization buffer can hold. The canonicalization step silently passes such URIs through with embedded ".." sequences intact, enabling path traversal in any consumer that later joins the URI with a filesystem path. Version 2.0.11 patches the issue.CVSS7.5HighEPSS0.50%RoutineCVE-2026-49848signalwire · freeswitch +1 moreFreeSWITCH: Pre-authentication `userVariables` injection in `mod_verto`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 1.11.1, mod_verto's check_auth userauth branch wrote request-supplied userVariables into the connection state before comparing the supplied password. The writes are append-only and the connection is not closed on a failed compare, so values declared on bad-password attempts persisted on the same WebSocket and carried into a subsequent successful login on that connection. This issue has been patched in version 1.11.1.CVSS4.3MediumEPSS0.17%PrioritiseCVE-2026-49847signalwire · freeswitch +1 moreFreeSWITCH: Stack overflow in bundled cJSON parser via deeply nested JSONFreeSWITCH 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 1.11.1, a single unauthenticated WebSocket frame containing a deeply nested JSON document crashes the FreeSWITCH process via stack overflow, terminating all calls and sessions on the host. The recursion drives the worker thread's stack pointer into the stack guard page, raising SIGSEGV from the kernel before any usable write primitive develops. This issue has been patched in version 1.11.1.CVSS7.5HighEPSS0.41%RoutineCVE-2026-49843signalwire · freeswitch +1 moreFreeSWITCH: Pre-authentication session eviction via attacker-chosen `sessid` in `mod_verto`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 1.11.1, mod_verto's JSON-RPC handler bound the connection to the client-supplied sessid on the first frame, before the authentication gate. Binding inserts the connection into the global session hash and, on a key collision, drops the prior occupant of that slot — sending it a verto.punt, detaching its calls, and closing its socket. An unauthenticated network attacker who knows a target session UUID could therefore evict the legitimate client. This issue has been patched in version 1.11.1.CVSS5.3MediumEPSS0.28%PrioritiseCVE-2026-49842signalwire · freeswitch +1 moreFreeSWITCH: Pre-authentication bandwidth amplification via `mod_verto` speed-test framesFreeSWITCH 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 1.11.1, mod_verto's WebSocket frame loop intercepts a #-prefixed speed-test protocol (#SPU / #SPB / #SPE) before any authentication check. The declared payload size in #SPU was parsed with atoi() and only rejected non-positive values, so an unauthenticated peer could request up to INT_MAX bytes. The server then wrote roughly size * 10 bytes back during the download phase, on the order of 20 GB per request, yielding strong outbound bandwidth amplification from a short request. This issue has been patched in version 1.11.1.CVSS7.5HighEPSS0.45%PrioritiseCVE-2026-49841signalwire · freeswitch +1 moreFreeSWITCH: Pre-authentication heap buffer overflow in `mod_verto` HTTP POST body readFreeSWITCH 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 1.11.1, the mod_verto HTTP request handler allocates a fixed 2 MiB buffer for a POST application/x-www-form-urlencoded body but accepts Content-Length up to just under 10 MiB. The body-read loop is bounded by Content-Length rather than the buffer size, producing an attacker-controlled heap overflow of up to ~8 MiB -- before the HTTP basic-auth check runs. This issue has been patched in version 1.11.1.CVSS9.8CriticalEPSS0.39%PrioritiseCVE-2026-49840signalwire · freeswitch +1 moreFreeSWITCH: Pre-authentication heap buffer overflow in libesl `Content-Length` parsingFreeSWITCH 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 1.11.1, esl_recv_event() parses Content-Length with atol() and passes the result straight to malloc(len + 1) with no sign or magnitude check. A malicious or man-in-the-middle ESL peer can send a frame with a negative Content-Length to corrupt the heap of, or crash, any process linked against libesl, before the client has authenticated to that peer. This issue has been patched in version 1.11.1.CVSS9.1CriticalEPSS0.31%PrioritiseCVE-2026-49475signalwire · freeswitch +1 moreFreeSWITCH: Out-of-bounds memory access in core STUN attribute parsingFreeSWITCH 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 1.11.0, a STUN packet whose declared attribute length is shorter than the structure the parser casts to causes the parser to read and write past the end of the attribute, producing an out-of-bounds memory access on the per-leg media buffer. This issue has been patched in version 1.11.0.CVSS7.5HighEPSS0.28%RoutineCVE-2026-49472signalwire · freeswitch +1 moreFreeSWITCH includes a vulnerable function, PREFIX(prologTok)() from libexpatFreeSWITCH 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 1.11.0, FreeSWITCH includes a vulnerable function, PREFIX(prologTok)(), in libs/xmlrpc-c/lib/expat/xmltok/xmltok_impl.c, which was cloned from an outdated and vulnerable version in libexpat/libexpat. The function did not receive the corresponding security patch. This issue has been patched in version 1.11.0.CVSS5.3MediumEPSS0.22%PrioritiseCVE-2026-45771signalwire · freeswitch +1 moreFreeswitch Denial-of-Service in SIP PUBLISH Requests via XML Entity ExpansionFreeSWITCH 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 1.11.0, FreeSWITCH's bundled XML parser expands nested <!ENTITY> declarations without a depth or count bound, so a small DTD can describe a body that expands exponentially ("billion laughs"). The PIDF body of a SIP PUBLISH is fed to this parser before any digest check, letting an unauthenticated network attacker force unbounded CPU and memory consumption with a single request. This issue has been patched in version 1.11.0.CVSS7.5HighEPSS0.34%PrioritiseCVE-2023-51443signalwire · freeswitch +2 moreFreeSWITCH susceptible to Denial of Service via DTLS Hello packets during call initiationFreeSWITCH 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 1.10.11, when handling DTLS-SRTP for media setup, FreeSWITCH is susceptible to Denial of Service due to a race condition in the hello handshake phase of the DTLS protocol. This attack can be done continuously, thus denying new DTLS-SRTP encrypted calls during the attack. If an attacker manages to send a ClientHello DTLS message with an invalid CipherSuite (such as `TLS_NULL_WITH_NULL_NULL`) to the port on the FreeSWITCH server that is expecting packets from the caller, a DTLS error is generated. This results in the media session being torn down, which is followed by teardown at signaling (SIP) level too. Abuse of this vulnerability may lead to a massive Denial of Service on vulnerable FreeSWITCH servers for calls that rely on DTLS-SRTP. To address this vulnerability, upgrade FreeSWITCH to 1.10.11 which includes the security fix. The solution implemented is to drop all packets from addresses that have not been validated by an ICE check.CVSS7.5HighEPSS1.49%PrioritiseCVE-2023-40019signalwire · freeswitch +1 moreFreeSWITCH allows authorized users to cause a denial of service attack by sending re-INVITE with SDP containing duplicate codec namesFreeSWITCH 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.CVSS7.5HighEPSS0.91%PrioritiseCVE-2023-40018signalwire · freeswitch +1 moreFreeSWITCH allows remote users to trigger out of bounds write by offering an ICE candidate with unknown component IDFreeSWITCH 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 remote users to trigger out of bounds write by offering an ICE candidate with unknown component ID. When an SDP is offered with any ICE candidates with an unknown component ID, FreeSWITCH will make an out of bounds write to its arrays. By abusing this vulnerability, an attacker is able to corrupt FreeSWITCH memory leading to an undefined behavior of the system or a crash of it. Version 1.10.10 contains a patch for this issue.CVSS7.5HighEPSS0.99%PrioritiseCVE-2023-32307freeswitch · sofia-sip +5 moreheap-over-flow and integer-overflow in sofia-sipSofia-SIP is an open-source SIP User-Agent library, compliant with the IETF RFC3261 specification.
Referring to [GHSA-8599-x7rq-fr54](https://github.com/freeswitch/sofia-sip/security/advisories/GHSA-8599-x7rq-fr54), several other potential heap-over-flow and integer-overflow in stun_parse_attr_error_code and stun_parse_attr_uint32 were found because the lack of attributes length check when Sofia-SIP handles STUN packets. The previous patch of [GHSA-8599-x7rq-fr54](https://github.com/freeswitch/sofia-sip/security/advisories/GHSA-8599-x7rq-fr54) fixed the vulnerability when attr_type did not match the enum value, but there are also vulnerabilities in the handling of other valid cases. The OOB read and integer-overflow made by attacker may lead to crash, high consumption of memory or even other more serious consequences. These issue have been addressed in version 1.13.15. Users are advised to upgrade.CVSS7.5HighEPSS1.06%PrioritiseCVE-2023-22741freeswitch · sofia-sip +5 moreheap-over-flow in stun_parse_attribute in sofia-sipSofia-SIP is an open-source SIP User-Agent library, compliant with the IETF RFC3261 specification. In affected versions Sofia-SIP **lacks both message length and attributes length checks** when it handles STUN packets, leading to controllable heap-over-flow. For example, in stun_parse_attribute(), after we get the attribute's type and length value, the length will be used directly to copy from the heap, regardless of the message's left size. Since network users control the overflowed length, and the data is written to heap chunks later, attackers may achieve remote code execution by heap grooming or other exploitation methods. The bug was introduced 16 years ago in sofia-sip 1.12.4 (plus some patches through 12/21/2006) to in tree libs with git-svn-id: http://svn.freeswitch.org/svn/freeswitch/trunk@3774 d0543943-73ff-0310-b7d9-9358b9ac24b2. Users are advised to upgrade. There are no known workarounds for this vulnerability.CVSS9.8CriticalEPSS2.48%PrioritiseCVE-2022-31003freeswitch · sofia-sip +5 moreHeap-based Buffer Overflow and Out-of-bounds Write in Sofia-SIPSofia-SIP is an open-source Session Initiation Protocol (SIP) User-Agent library. Prior to version 1.13.8, when parsing each line of a sdp message, `rest = record + 2` will access the memory behind `\0` and cause an out-of-bounds write. An attacker can send a message with evil sdp to FreeSWITCH, causing a crash or more serious consequence, such as remote code execution. Version 1.13.8 contains a patch for this issue.CVSS9.8CriticalEPSS4.11%PrioritiseCVE-2022-31002freeswitch · sofia-sip +5 moreOut-of-bounds Read in Sofia-SIPSofia-SIP is an open-source Session Initiation Protocol (SIP) User-Agent library. Prior to version 1.13.8, an attacker can send a message with evil sdp to FreeSWITCH, which may cause a crash. This type of crash may be caused by a URL ending with `%`. Version 1.13.8 contains a patch for this issue.CVSS7.5HighEPSS1.93%PrioritiseCVE-2022-31001freeswitch · sofia-sip +6 moreOut-of-bounds Read in Sofia-SIPSofia-SIP is an open-source Session Initiation Protocol (SIP) User-Agent library. Prior to version 1.13.8, an attacker can send a message with evil sdp to FreeSWITCH, which may cause crash. This type of crash may be caused by `#define MATCH(s, m) (strncmp(s, m, n = sizeof(m) - 1) == 0)`, which will make `n` bigger and trigger out-of-bound access when `IS_NON_WS(s[n])`. Version 1.13.8 contains a patch for this issue.CVSS7.5HighEPSS2.22%RoutineCVE-2021-41158signalwire · freeswitch +2 moreFreeSWITCH vulnerable to SIP digest leak for configured gatewaysFreeSWITCH 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 1.10.7, an attacker can perform a SIP digest leak attack against FreeSWITCH and receive the challenge response of a gateway configured on the FreeSWITCH server. This is done by challenging FreeSWITCH's SIP requests with the realm set to that of the gateway, thus forcing FreeSWITCH to respond with the challenge response which is based on the password of that targeted gateway. Abuse of this vulnerability allows attackers to potentially recover gateway passwords by performing a fast offline password cracking attack on the challenge response. The attacker does not require special network privileges, such as the ability to sniff the FreeSWITCH's network traffic, to exploit this issue. Instead, what is required for this attack to work is the ability to cause the victim server to send SIP request messages to the malicious party. Additionally, to exploit this issue, the attacker needs to specify the correct realm which might in some cases be considered secret. However, because many gateways are actually public, this information can easily be retrieved. The vulnerability appears to be due to the code which handles challenges in `sofia_reg.c`, `sofia_reg_handle_sip_r_challenge()` which does not check if the challenge is originating from the actual gateway. The lack of these checks allows arbitrary UACs (and gateways) to challenge any request sent by FreeSWITCH with the realm of the gateway being targeted. This issue is patched in version 10.10.7. Maintainers recommend that one should create an association between a SIP session for each gateway and its realm to make a check be put into place for this association when responding to challenges.CVSS7.5HighEPSS0.83%