CVE-2026-57159 — PJSIP: SDP parser out-of-bounds write in remote payload-type map maintenance
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.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.6% (30-day exploitation probability)+7
- Technical severity (high)+6
- Automatable exploitation (SSVC)+3
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
CISA SSVC assessment CISA
Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
- Documented patch — github.com (NIST National Vulnerability Database)
- Documented patch — github.com (NIST National Vulnerability Database)
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Pjsip Pjproject, Teluu Pjsip).
- The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
- Apply the fixed version or the patch documented under Remediation.
- Search available logs for exploit probes, errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 8.4 | CVSS 4.0 | High | — | — | security-advisories@github.com via NIST National Vulnerability Database |
| 8.4 | CVSS 4.0 | High | — | — | GitHub_M via CVE Program (cve.org) e CISA ADP |
| 7.5 | CVSS 3.1 | High | 3.9 | 3.6 | nvd@nist.gov via NIST National Vulnerability Database |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H (score shown at the top: nvd@nist.gov) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · pjsip/pjproject
- SSVC assessment updated
- Record published
- Fix documented
- CVSS changed · 7.5
- Source status changed · → Analyzed
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 15, 2026 – Oct 15, 2026
References
2 on the record
Elsewhere on this site
Related CVEs (same products)
- High CVE-2026-84975 PJSIP: TLS server identity (hostname) verification bypass via embedded NUL in certificate SubjectAltName (OpenSSL and GnuTLS backends) 27d
- Medium CVE-2026-77396 PJSIP: Heap buffer overflow in the AVI parser 27d
- Medium CVE-2026-57166 PJSIP: Pre-authentication overflow in the telnet CLI error Sep 4, 2026
- Critical CVE-2026-57162 PJSIP: Stack overflow parsing SDP a=crypto attributes Sep 4, 2026
- Medium CVE-2026-57164 PJSIP: Heap overflow in the HTTP client Sep 4, 2026
- Critical CVE-2026-57163 PJSIP: Stack overflow parsing a TLS peer certificate's SubjectAltName in GnuTLS backend Sep 4, 2026
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2026-57159 is "PJSIP: SDP parser out-of-bounds write in remote payload-type map maintenance", rated High. It affects Pjproject (Pjsip); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 7.5 describes technical severity. EPSS 0.60% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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