debugmcp mcp-debugger server.ts handleGetSourceContext path traversal

published 2026-05-25 5 mo ago modified 2026-07-23 3 mo ago also EUVD-2026-31697

cvss: 4.3; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.4%; EPSS 0.4% chance of exploitation in 30 days, percentile 38%
public exploits: 0; none known

A vulnerability was identified in debugmcp mcp-debugger up to 0.20.0. Impacted is the function handleGetSourceContext of the file src/server.ts. The manipulation leads to path traversal. The attack is possible to be carried out remotely. The exploit is publicly available and might be used. The vendor was contacted early about this disclosure but did not respond in any way.

CISA SSVC

Exploitation: Proof of concept is public
Automatable: no
Technical impact: partial
Assessed: 5 mo ago (2026-05-26)

Exploit prediction

0.44% chance of exploitation in the next 30 days, higher than 38% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

github.com https://github.com/hyk6225/public_exp/issues/1 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	4.0	5.3	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:P
CNA	3.1	4.3	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N/E:P/RL:X/RC:R
CNA	3.0	4.3	CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N/E:P/RL:X/RC:R
CNA	2.0	4.0	AV:N/AC:L/Au:S/C:P/I:N/A:N/E:POC/RL:ND/RC:UR
CNA	4.0	2.1	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:P/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
CNA	3.1	4.3	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
CNA	2.0	4.0	AV:N/AC:L/Au:S/C:P/I:N/A:N

Affected products

debugmcp mcp-debugger

Classification

Weakness

CWE-22 Improper Limitation of a Pathname to a Restricted Directory

References

github.com /hyk6225/public_exp/issues/1
exploit, issue-tracking
vuldb.com /vuln/365448
vdb-entry, technical-description
vuldb.com /vuln/365448/cti
signature, permissions-required
vuldb.com /submit/813980
third-party-advisory

Sources

CVE List CVE-2026-9467
NVD CVE-2026-9467

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary