PJSIP: Pre-authentication overflow in the telnet CLI error
Published Sep 4, 2026
6.3
MEDIUMCVSS 4.0
EPSS 0.53%
Description
PJSIP is a free and open source multimedia communication library written in C. Prior to commit 4472a31, a stack buffer overflow exists in the PJLIB-UTIL telnet CLI front-end when rendering feedback for an entered command line. Several command-line handling paths write an attacker-influenced amount of data into fixed-size buffers without sufficient bounds checking, so a long command line can overflow them. This affects only applications that enable the telnet CLI front-end (e.g. pj_cli_telnet_create() / --cli-telnet-port). The telnet CLI is an interactive administration interface with no authentication, so any client able to reach it can already issue arbitrary CLI commands. A malformed or overly long command line can overflow a fixed-size stack buffer while rendering command-line feedback, which may lead to application termination. Because reaching this code already requires access to the unauthenticated CLI, the impact beyond that existing access is limited. Applications that do not enable the telnet CLI front-end are not affected. This issue has been patched via commit 4472a31.
Affected products
-
- Version < 4472a31d77a7506ff175dad5abef490f4e31bed1StatusaffectedConstraints-
- Version
No data.
No Red Hat product state for this CVE.
No package ranges for this CVE.
Remediation
No remediation recorded yet.
Metrics
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
1 other source (NVD) ▾
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/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
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
No CVSS v3.0 score for this CVE.
No CVSS v2.0 score for this CVE.
This CVE is not in the KEV list.
CISA SSVC (Vulnrichment)
Stakeholder-Specific Vulnerability Categorization from CISA ADP.
Exploitation
NoneAutomatable
YesTechnical Impact
PartialDecision
n/aAssessed Sep 9, 2026 · SSVC 2.0.3
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
Score over time
Sep–Oct 2026- EPSS v5
Percentile over time
- EPSS v5
Table of values (2 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 0.53% (0.00533) | 42.90th | v5 (v2026.06.15) |
| Sep 5, 2026 | 0.44% (0.00437) | 36.59th | v5 (v2026.06.15) |
References (2)
- https://github.com/pjsip/pjproject/commit/4472a31d77a7506ff175dad5abef490f4e31bed1 x_refsource_MISCPatch
- https://github.com/pjsip/pjproject/security/advisories/GHSA-9c8q-h38q-p85j x_refsource_CONFIRMPatchVendor Advisory
| Link | Providers | Tags |
|---|---|---|
| https://github.com/pjsip/pjproject/commit/4472a31d77a7506ff175dad5abef490f4e31bed1 | x_refsource_MISCPatch | |
| https://github.com/pjsip/pjproject/security/advisories/GHSA-9c8q-h38q-p85j | x_refsource_CONFIRMPatchVendor Advisory |
Change history (0)
No recorded changes yet.