CVE-2026-114140

HIGH
MEDIUM Priority: 0.03 BB Relevance: 58/100
Published: 2026-10-21 Modified: 2026-10-22 First seen: 2026-10-29 Status: active

Attack Surface

Network Low Complexity Conf. Impact Integ. Impact

CVSS Vector Breakdown

AV: Network
AC: Low
PR: Low
UI: Active
S: X
AT: Present
VC: High
VI: High
VA: High

Description

The nbconvert tool, jupyter nbconvert, converts Jupyter notebooks to various other formats via Jinja templates. From 5.4.0 until 7.17.2, ExtractOutputPreprocessor in nbconvert/preprocessors/extractoutput.py joins the attacker-controlled cell output metadata filename to output_files_dir without limiting the result to the intended directory. When a victim converts a malicious notebook with the markdown, LaTeX, reStructuredText, or AsciiDoc exporter, path traversal in the output filename can write attacker-controlled output data to arbitrary locations accessible to the victim. Running the notebook cell again replaces the malicious output metadata, but merely converting the supplied notebook does not. This issue is fixed in version 7.17.2.

Weakness Classification (1)

Bug Bounty Relevance

58 / 100
✓ Network accessible
✓ Low complexity

CVSS Score

8.8 / 10.0 v4.0
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:A/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/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

EPSS — Exploitation Probability

0.38%
Raw Score 0.003810
Percentile 32.1%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00381
2026-10-28
0.00381

Intelligence Sources

nvd ref →