CVE-2026-35347 | uutils coreutils comm Silent Data Loss or Denial of Service via Improper Input Validation

The comm utility in uutils coreutils incorrectly consumes data from non-regular file inputs before performing comparison operations. The are_files_identical function opens and reads from both input paths to compare content without first verifying if the paths refer to regular files. If an input path is a FIFO or a pipe, this pre-read operation drains the stream, leading to silent data loss before the actual comparison logic is executed. Additionally, the utility may hang indefinitely if it attempts to pre-read from infinite streams like /dev/zero.

Published: 2026-04-22 Last update: 2026-04-27 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-35347 is rated Low Risk (19.4/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.02%). 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-2026-35347

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 0.02%

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-35347

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
4.4 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L 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:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
1.8 2.5 [email protected]

Weakness enumeration for CVE-2026-35347

GitHub Security Advisory for CVE-2026-35347

GHSA-rx8h-33gr-vhj9 · Severity: medium · Ecosystem: rust — uutils coreutils' comm utility incorrectly consumes data from non-regular file inputs before performing comparison operations

OS Trackers for CVE-2026-35347

vendor priority summary link
debian not yet assigned CVE-2026-35347 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-2026-35347
ubuntu medium CVE-2026-35347 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-2026-35347

Affected software / configurations for CVE-2026-35347

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

References for CVE-2026-35347

cvelogic Threat Intelligence