Quick answer
Direct answer
Risk scores
| CVSS metric | What it means |
|---|---|
| Attack vector (AV:N) | Network: reachable remotely |
| Attack complexity (AC:L) | Low complexity |
| Attack requirements (AT:N) | No attack requirements |
| Privileges required (PR:N) | No privileges required |
| User interaction (UI:N) | No user interaction |
| Confidentiality (VC:N) | No confidentiality impact |
| Integrity (VI:H) | High integrity impact |
| Availability (VA:H) | High availability impact |
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
About Teluu Pjsip
CVE-2026-57163 affects Teluu Pjsip, a product from Teluu. Before acting, confirm where Teluu Pjsip runs in your estate, who owns it and whether it is reachable from the internet, because exposure decides real risk more than the score alone.
What the flaw is
In plain terms: PJSIP is a free and open source multimedia communication library written in C. Prior to commit c4a151a, a stack buffer overflow exists in the GnuTLS TLS backend when parsing the Subject Alternative Name extension of a peer certificate (tls_cert_get_info() in ssl_sock_gtls.c). Only GnuTLS builds are affected (--with-gnutls); OpenSSL and Apple SecureTransport/Network.framework builds are not affected. While extracting certificate information after a TLS handshake, an incorrect buffer-size value can cause an oversized SubjectAltName entry to be written past the end of a fixed-size stack buffer. A network-positioned attacker presenting a crafted certificate — a malicious server to a connecting client, or a malicious client to a server that requests certificates — can trigger this during the TLS handshake, before any SIP-level authentication. Impact may range from unexpected application termination to control flow hijack/memory corruption. This issue has been patched via commit c4a151a.
The weakness class is Stack Buffer Overflow. A write past the end of a stack buffer can corrupt control data.
Based on its CVSS vector, the flaw can be reached over the network, needs no login, and needs no user interaction. Apply the vendor fix and confirm exposure on internet facing and business critical assets first.
Affected versions and timeline
| Field | Detail |
|---|---|
| Product | Teluu Pjsip |
| Affected versions | Pjsip up to and including 2.17 |
| Published | Sep 4, 2026 |
| Last modified | Sep 11, 2026 |
| Added to CISA KEV | Not listed |
| Assigning CNA | security-advisories@github.com |
How to detect it
- Inventory every instance of Teluu Pjsip and record the running version against the affected range above.
- Check external attack surface scans for internet facing instances of the component.
- Review logs on affected systems for unusual requests, errors or new processes around the vulnerable function.
- Confirm with an authenticated vulnerability scan once your scanner has a check for this CVE.
How to fix it
- Apply the fixed version of Teluu Pjsip named in the vendor advisory.
- If patching must wait, restrict network access to the affected service and put it behind authentication or a web application firewall rule.
- Rescan after the change to prove the exposure is gone, then close the ticket.
CTEM action plan
| CTEM stage | What to do for this CVE |
|---|---|
| Scope | Add every business service that depends on Teluu Pjsip to the current CTEM cycle. |
| Discover | Find all instances, including shadow and cloud deployments, and record versions and exposure. |
| Prioritize | Rank using EPSS and CVSS together with asset exposure and business impact. |
| Validate | Confirm the flaw is reachable and exploitable in your environment and that compensating controls work. |
| Mobilize | Assign the fix to the asset owner with a due date matched to the priority, then verify closure. |
CWE References
- CWE-121: Stack Buffer Overflow More CVEs with this weakness
Technical References
Frequently asked questions
Related CVEs
PJSIP is a free and open source multimedia communication library written in C. Prior to commit a1b707c, a stack buffer overflow exists in the SRTP/SDES media transport when processing a=crypto attributes during SDP offer/answer (sdes_encode_sdp() in transport_srtp_sdes.c). This affects applications with SRTP enabled (use_srtp optional or mandatory, using SDES keying). During media negotiation, the crypto attributes from the remote SDP are collected into a fixed-size array without bounding their number; a remote peer that includes an excessive number of a=crypto attributes in a single media description can write past the end of that array on the stack. This is reachable from an incoming SIP INVITE during offer/answer, before application-level authentication. Impact may range from unexpected application termination to control flow hijack/memory corruption. Applications that do not enable SRTP are not affected. This issue has been patched via commit a1b707c.
PJSIP is a free and open source multimedia communication library written in C. Prior to commit acc03b5, a stack buffer overflow exists in PJSUA when processing Service-Route headers in a registration response (update_service_route() in pjsua_acc.c). This affects applications that register using the PJSUA/PJSUA2 account API (the default registration path). The Service-Route URIs from a 2xx response to REGISTER are stored into a fixed-size array without bounding the number of headers; a registrar that returns an excessive number of Service-Route headers can write past the end of the array on the stack. The values written are internal pointers rather than arbitrary data, so the most likely impact is unexpected application termination (denial of service), though memory corruption cannot be excluded. The malicious response may come from a compromised or malicious registrar, or — over unprotected transports — a spoofed response. This issue has been patched via commit acc03b5.
PJSIP is a free and open source multimedia communication library written in C. Prior to commit 673b978, a remote out-of-bounds read and write can occur in the SDP negotiator when the remote payload-type map maintenance feature is enabled. assign_pt_and_update_map() in pjmedia/src/pjmedia/sdp_neg.c uses payload-type numbers taken from a remote SDP offer or answer to index fixed-size internal tables without sufficient bounds validation, so a crafted remote SDP can cause memory access outside those tables. The practical impact is memory corruption and denial of service; code execution is not demonstrated. This path is only reached when PJMEDIA_SDP_NEG_MAINTAIN_REMOTE_PT_MAP is enabled. The default is disabled, so default builds are not affected; the feature is an interoperability option that integrating products may enable. This issue has been patched via commit 673b978.
PJSIP is a free and open source multimedia communication library written in C. In 2.16 and earlier, there is an integer overflow in media stream buffer size calculation when processing SDP with asymmetric ptime configuration. The overflow may result in an undersized buffer allocation, which can lead to unexpected application termination or memory corruption This vulnerability is fixed in 2.17.
Stack buffer overflow vulnerability in D-Link DIR-513 v1.10 via the curTime parameter to goform/formSetDomainFilter.
Stack buffer overflow vulnerability in D-Link DIR-513 v1.10 via the curTime parameter to goform/formSetPortTr.
Earn your free CTEM certification.
Learn to scope, prioritize, validate and mobilize fixes for CVEs like CVE-2026-57163 with a free CTEM certification.
Beginner / Practitioner / Program Leader
Explore certifications