CVE-2026-35374 | uutils coreutils split Arbitrary File Truncation via Time-of-Check to Time-of-Use (TOCTOU) Race Condition

A Time-of-Check to Time-of-Use (TOCTOU) vulnerability exists in the split utility of uutils coreutils. The program attempts to prevent data loss by checking for identity between input and output files using their file paths before initiating the split operation. However, the utility subsequently opens the output file with truncation after this path-based validation is complete. A local attacker with write access to the directory can exploit this race window by manipulating mutable path components (e.g., swapping a path with a symbolic link). This can cause split to truncate and write to an unintended target file, potentially including the input file itself or other sensitive files accessible to the process, leading to permanent data loss.

Published: 2026-04-22 Last update: 2026-05-04 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-35374 is rated Low Risk (25.8/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.01%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

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-2026-35374

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-2026-35374

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.3 3.1 MEDIUM
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:H 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:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
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:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.0 5.2 [email protected]

Weakness enumeration for CVE-2026-35374

GitHub Security Advisory for CVE-2026-35374

GHSA-4wrp-79m8-9m9p · Severity: medium · Ecosystem: rust — uutils coreutils has a Time-of-check Time-of-use (TOCTOU) Race Condition

OS Trackers for CVE-2026-35374

vendor priority summary link
debian not yet assigned CVE-2026-35374 not yet assigned priority: Debian including 1 source packages (rust-coreutils), 3 status rows across 3 suites (bookworm, sid, trixie): open 3. https://security-tracker.debian.org/tracker/CVE-2026-35374
ubuntu medium CVE-2026-35374 medium priority: Ubuntu including 1 source packages (rust-coreutils), 5 status rows across 5 suites (jammy, noble, questing, resolute, upstream): needed 4, DNE 1. https://ubuntu.com/security/CVE-2026-35374

Affected software / configurations for CVE-2026-35374

Vendor Product Version Raw CPE
uutils coreutils — cpe:2.3:a:uutils:coreutils:-:*:*:*:*:rust:*:*

References for CVE-2026-35374

cvelogic Threat Intelligence