CVE-2026-44028

An issue was discovered in Nix before 2.34.7 and Lix before 2.95.2. Unbounded recursion in the NAR (Nix Archive) parser could lead to a stack-to-heap overflow when the parser is run on a coroutine stack. The stack is allocated without a guard page, which means that a stack overflow could overwrite memory on the heap and could allow arbitrary code execution as the Nix daemon (run as root in multi-user installations) if ASLR hardening is bypassed. This can be exploited by all users able to connect to the daemon (e.g., in Nix, this is configurable via the allowed-users setting, defaulting to all users). The fixed versions are 2.34.7, 2.33.6, 2.32.8, 2.31.5, 2.30.5, 2.29.4, and 2.28.7 for Nix (introduced in 2.24.4); and 2.95.2, 2.94.2, and 2.93.4 for Lix (introduced in 2.93.0).

Published: 2026-05-05 Last update: 2026-05-09 Assigner: [email protected] Source: [email protected]
NVD Status：Deferred，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-44028 is rated Low Risk (30.1/100): CVSS High 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-2026-44028

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 2026-05-05 — 0.01% —

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-44028

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/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: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:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
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:N)
Service keeps running; no real outage angle.
 1.1 5.8 [email protected]

Weakness enumeration for CVE-2026-44028

GitHub Security Advisory for CVE-2026-44028

GHSA-jggj-j5fq-x969 · Severity: high — An issue was discovered in Nix before 2.34.7 and Lix before 2.95.2. Unbounded recursion in the...

OS Trackers for CVE-2026-44028

vendor priority summary link
debian unimportant CVE-2026-44028 unimportant priority: Debian including 1 source packages (nix), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): open 3, resolved 2. https://security-tracker.debian.org/tracker/CVE-2026-44028
suse high CVE-2026-44028 severity important: SUSE including 5 source package names (nix-2.34.7-1.1, nix-bash-completion-2.34.7-1.1, nix-devel-2.34.7-1.1, nix-fish-completion-2.34.7-1.1, nix-zsh-completion-2.34.7-1.1), 5 product×package rows across 1 product lines (openSUSE Tumbleweed): Fixed 5. https://www.suse.com/security/cve/CVE-2026-44028/
ubuntu medium CVE-2026-44028 medium priority: Ubuntu including 1 source packages (nix), 5 status rows across 5 suites (jammy, noble, questing, resolute, upstream): needs-triage 5. https://ubuntu.com/security/CVE-2026-44028

Affected software / configurations for CVE-2026-44028

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2026-44028

cvelogic Threat Intelligence