CVE-2026-35355 | uutils coreutils install Arbitrary File Overwrite via Symlink TOCTOU Race

Exp

The install utility in uutils coreutils is vulnerable to a Time-of-Check to Time-of-Use (TOCTOU) race condition during file installation. The implementation unlinks an existing destination file and then recreates it using a path-based operation without the O_EXCL flag. A local attacker can exploit the window between the unlink and the subsequent creation to swap the path with a symbolic link, allowing them to redirect privileged writes to overwrite arbitrary system files.

Published: 2026-04-22 Last update: 2026-04-27 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-35355 is rated Exploit Available (50/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.12%). 1 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

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

Public exploit references (Exploit-DB) for CVE-2026-35355

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2026-35355

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 2026-06-15 0.01% 0.12% +0.10%
2 2026-04-23 — 0.01% —

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-35355

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-2026-35355

GitHub Security Advisory for CVE-2026-35355

GHSA-v24v-f45g-w7jf · Severity: medium · Ecosystem: rust — uutils coreutils has a Time-of-Check to Time-of-Use (TOCTOU) race condition

OS Trackers for CVE-2026-35355

vendor priority summary link
debian not yet assigned CVE-2026-35355 not yet assigned priority: Debian including 1 source packages (rust-coreutils), 4 status rows across 4 suites (bookworm, forky, sid, trixie): open 2, resolved 2. https://security-tracker.debian.org/tracker/CVE-2026-35355
ubuntu medium CVE-2026-35355 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-2026-35355

Affected software / configurations for CVE-2026-35355

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

References for CVE-2026-35355

cvelogic Threat Intelligence