CVE-2026-26158 | Busybox: busybox: arbitrary file modification and privilege escalation via unvalidated tar archive entries

A flaw was found in BusyBox. This vulnerability allows an attacker to modify files outside of the intended extraction directory by crafting a malicious tar archive containing unvalidated hardlink or symlink entries. If the tar archive is extracted with elevated privileges, this flaw can lead to privilege escalation, enabling an attacker to gain unauthorized access to critical system files.

Published: 2026-02-11 Last update: 2026-06-02 Assigner: [email protected] Source: [email protected]
NVD Status：Deferred，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-26158 is rated Low Risk (28.1/100): CVSS High severity, with low exploitation likelihood (EPSS 0.00%). 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-2026-26158

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 2026-02-12 — 0.00% —

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-26158

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.0 3.1 HIGH
CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/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:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big 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 5.9 [email protected]

Weakness enumeration for CVE-2026-26158

GitHub Security Advisory for CVE-2026-26158

GHSA-r8f8-4pgh-4m8v · Severity: high — A flaw was found in BusyBox. This vulnerability allows an attacker to modify files outside of the...

OS Trackers for CVE-2026-26158

vendor priority summary link
debian not yet assigned CVE-2026-26158 not yet assigned priority: Debian including 1 source packages (busybox), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): open 3, resolved 2. https://security-tracker.debian.org/tracker/CVE-2026-26158
redhat high — https://access.redhat.com/security/cve/CVE-2026-26158
suse high CVE-2026-26158 severity important: SUSE including 106 source package names (13.2-9.19:coreutils-9.4-5.1, 2.1.3-6.58:coreutils-9.4-5.1, …), 221 product×package rows across 61 product lines (Container suse/sl-micro/6.0/baremetal-iso-image, Container suse/sl-micro/6.0/baremetal-os-container, … (61 product lines)): Fixed 218, First Fixed 3. https://www.suse.com/security/cve/CVE-2026-26158/
ubuntu medium CVE-2026-26158 medium priority: Ubuntu including 1 source packages (busybox), 8 status rows across 8 suites (bionic, focal, jammy, noble, questing, trusty, upstream, xenial): needs-triage 8. https://ubuntu.com/security/CVE-2026-26158

Affected software / configurations for CVE-2026-26158

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2026-26158

cvelogic Threat Intelligence