CVE-2023-38703 | PJSIP has use-after-free vulnerability in SRTP media transport

PJSIP is a free and open source multimedia communication library written in C with high level API in C, C++, Java, C#, and Python languages. SRTP is a higher level media transport which is stacked upon a lower level media transport such as UDP and ICE. Currently a higher level transport is not synchronized with its lower level transport that may introduce use-after-free issue. This vulnerability affects applications that have SRTP capability (`PJMEDIA_HAS_SRTP` is set) and use underlying media transport other than UDP. This vulnerability’s impact may range from unexpected application termination to control flow hijack/memory corruption. The patch is available as a commit in the master branch.

Published: 2023-10-06 Last update: 2025-04-10 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2023-38703 is rated Moderate Risk (57/100): CVSS Critical severity, with medium exploitation likelihood (EPSS 0.28%). Mandatory action: Review affected assets and schedule remediation.

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

Exploit prediction scoring system (EPSS) score for CVE-2023-38703

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 2026-03-02 0.38% 0.28% -0.10%
2 2025-11-21 0.90% 0.38% -0.52%
3 2025-11-18 0.90%

Full EPSS history (11 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-38703

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/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:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
3.9 5.9 [email protected]
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/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:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
3.9 5.9 [email protected]

Weakness enumeration for CVE-2023-38703

OS Trackers for CVE-2023-38703

vendor priority summary link
alpine CVE-2023-38703: 1 source package rows (pjproject); 6 state rows across 6 repos (3.18-main, 3.19-main, 3.20-main, 3.21-main, 3.22-main, edge-main); fixed 6, open 0. https://security.alpinelinux.org/vuln/CVE-2023-38703
debian unimportant CVE-2023-38703 unimportant priority: Debian including 2 source packages (asterisk, ring), 4 status rows across 3 suites (bookworm, bullseye, sid): open 2, resolved 2. https://security-tracker.debian.org/tracker/CVE-2023-38703
ubuntu medium CVE-2023-38703 medium priority: Ubuntu including 2 source packages (asterisk, ring), 24 status rows across 12 suites (bionic, focal, jammy, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): needs-triage 10, ignored 9, DNE 5. https://ubuntu.com/security/CVE-2023-38703

Affected software / configurations for CVE-2023-38703

Vendor Product Version Raw CPE
teluu pjsip <= 2.13.1 cpe:2.3:a:teluu:pjsip:*:*:*:*:*:*:*:*

References for CVE-2023-38703

cvelogic Threat Intelligence