CVE-2026-35342 | uutils coreutils mktemp Insecure Temporary File Placement via Empty TMPDIR

The mktemp utility in uutils coreutils fails to properly handle an empty TMPDIR environment variable. Unlike GNU mktemp, which falls back to /tmp when TMPDIR is an empty string, the uutils implementation treats the empty string as a valid path. This causes temporary files to be created in the current working directory (CWD) instead of the intended secure temporary directory. If the CWD is more permissive or accessible to other users than /tmp, it may lead to unintended information disclosure or unauthorized access to temporary data.

Published: 2026-04-22 Last update: 2026-05-04 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-35342 is rated Low Risk (14.1/100): CVSS Low severity, with low exploitation likelihood (EPSS 0.01%). Mandatory action: Low composite risk—no urgent action required; patch on your normal maintenance cycle and revisit priority if CVSS or EPSS increases.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-35342

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-04-23 0.01%

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-35342

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
3.3 3.1 LOW
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
1.8 1.4 [email protected]

Weakness enumeration for CVE-2026-35342

GitHub Security Advisory for CVE-2026-35342

GHSA-2cxp-xq3c-mjxx · Severity: low · Ecosystem: rust — uutils coreutils' mktemp utility doesn't properly handle an empty TMPDIR environment variable

OS Trackers for CVE-2026-35342

vendor priority summary link
debian not yet assigned CVE-2026-35342 not yet assigned priority: Debian including 1 source packages (rust-coreutils), 3 status rows across 3 suites (bookworm, sid, trixie): open 2, resolved 1. https://security-tracker.debian.org/tracker/CVE-2026-35342
ubuntu medium CVE-2026-35342 medium priority: Ubuntu including 1 source packages (rust-coreutils), 5 status rows across 5 suites (jammy, noble, questing, resolute, upstream): needed 2, DNE 1, not-affected 1, released 1. https://ubuntu.com/security/CVE-2026-35342

Affected software / configurations for CVE-2026-35342

Vendor Product Version Raw CPE
uutils coreutils < 0.6.0 cpe:2.3:a:uutils:coreutils:*:*:*:*:*:rust:*:*

References for CVE-2026-35342

cvelogic Threat Intelligence