Dashboard / CVE-2026-121520

CVE-2026-121520

MEDIUM
MEDIUM Priority: 0.01 BB Relevance: 29/100
Published: 2026-11-03 Modified: 2026-11-06 First seen: 2026-11-03 Status: active

Attack Surface

Low Complexity No Interaction

CVSS Vector Breakdown

AV: Local
AC: Low
PR: High
UI: None
S: X
AT: Present
VC: None
VI: None
VA: None

Description

In BuildKit versions prior to v0.34.1, a malicious client with access to the BuildKit control APIs can submit a build request that sets an extended attribute on a file outside the BuildKit state directory. Extended attributes in the trusted. or security. namespaces may also be set, potentially giving a program on the host elevated privileges. This issue affects build services that accept build requests from untrusted users. The issue is fixed in v0.34.1.

Weakness Classification (1)

Affected Software (2)

VendorProductVersion
Moby BuildKit 0 < 0.34.1
Moby BuildKit 0 < 0.34.1

References & Advisories (1)

Bug Bounty Relevance

29 / 100
✓ Low complexity
✓ No user interaction

CVSS Score

4.5 / 10.0 v4.0
CVSS:4.0/AV:L/AC:L/AT:P/PR:H/UI:N/VC:N/VI:N/VA:N/SC:N/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

0.14%
Raw Score 0.001390
Percentile 3.3%
Date 2026-11-13

EPSS Trend

2026-11-13
0.00139
2026-11-12
0.00139
2026-11-10
0.00139
2026-11-09
0.00139
2026-11-08
0.00139
2026-11-07
0.00139
2026-11-06
0.00139
2026-11-05
0.00139
2026-11-04
0.00139

Intelligence Sources

mitre ref →
nvd ref →

External Links