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Fencer Intel
medium 5.3

CVE-2026-81486 json

bsmi021 mcp-file-context-server Path Resolution index.ts read_context path traversal

published 2mo ago modified 2mo ago also EUVD-2026-66833

cvss
5.3
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.7%
EPSS 0.7% chance of exploitation in 30 days, percentile 53%
public exploits
0
none known

Summary

A vulnerability was detected in bsmi021 mcp-file-context-server 1.0.0. Affected by this issue is the function read_context of the file src/index.ts of the component Path Resolution. Performing a manipulation of the argument path results in path traversal. It is possible to initiate the attack remotely. The exploit is now public and may be used. The project was informed of the problem early through an issue report but has not responded yet.

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CISA SSVC

Exploitation
Proof of concept is public
Automatable
yes
Technical impact
partial
Assessed
2mo ago

Exploit prediction

0.69% chance of exploitation in the next 30 days, higher than 53% of all scored CVEs (FIRST EPSS, 2026-11-11).

Exploits and checks

  • vuldb.com https://vuldb.com/submit/887137 referenced PoC, tagged "exploit" by a source, unverified
  • github.com https://github.com/bsmi021/mcp-file-context-server/issues/15 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 4.0 6.9 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:P
CNA 3.1 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N/E:P/RL:X/RC:R
CNA 3.0 5.3 CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N/E:P/RL:X/RC:R
CNA 2.0 5.0 AV:N/AC:L/Au:N/C:P/I:N/A:N/E:POC/RL:ND/RC:UR
CNA 4.0 5.5 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/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 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
CNA 2.0 5.0 AV:N/AC:L/Au:N/C:P/I:N/A:N

Affected products

  • bsmi021 mcp-file-context-server

Classification

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

References

Sources

Fencer Intel 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.