CVE-2026-35346 | uutils coreutils comm Silent Data Corruption via Lossy UTF-8 Normalization

Exp

The comm utility in uutils coreutils silently corrupts data by performing lossy UTF-8 conversion on all output lines. The implementation uses String::from_utf8_lossy(), which replaces invalid UTF-8 byte sequences with the Unicode replacement character (U+FFFD). This behavior differs from GNU comm, which processes raw bytes and preserves the original input. This results in corrupted output when the utility is used to compare binary files or files using non-UTF-8 legacy encodings.

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

Conclusion & alert: CVE-2026-35346 is rated Exploit Available (50/100): CVSS Low severity, with low exploitation likelihood (EPSS 0.18%). Core evidence: 1 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: 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-2026-35346

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

Exploit prediction scoring system (EPSS) score for CVE-2026-35346

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% 0.18% +0.16%
2 2026-04-23 0.01%

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-35346

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:N/I:L/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: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:N)
Service keeps running; no real outage angle.
1.8 1.4 [email protected]

Weakness enumeration for CVE-2026-35346

GitHub Security Advisory for CVE-2026-35346

GHSA-hwhf-8p2f-45wr · Severity: low · Ecosystem: rust — coreutils' comm utility silently corrupts data by performing lossy UTF-8 conversion on all output lines

OS Trackers for CVE-2026-35346

vendor priority summary link
debian not yet assigned CVE-2026-35346 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-2026-35346
ubuntu medium CVE-2026-35346 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-2026-35346

Affected software / configurations for CVE-2026-35346

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

References for CVE-2026-35346

cvelogic Threat Intelligence