NixOS Nix/Lix NAR Parser recursion

CVSS Meta Temp Score
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CTI Interest Score
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5.9$0-$5k0.00

Summaryinfo

A vulnerability was found in NixOS Nix and Lix. It has been declared as problematic. Impacted is an unknown function of the component NAR Parser. The manipulation results in recursion. This vulnerability is known as CVE-2026-44028. Attacking locally is a requirement. No exploit is available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic has been found in NixOS Nix and Lix (version now known). Affected is some unknown processing of the component NAR Parser. The manipulation with an unknown input leads to a recursion vulnerability. CWE is classifying the issue as CWE-674. The product does not properly control the amount of recursion that takes place, consuming excessive resources, such as allocated memory or the program stack. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

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).

The advisory is shared for download at discourse.nixos.org. This vulnerability is traded as CVE-2026-44028 since 05/05/2026. The exploitability is told to be difficult. The attack needs to be approached locally. There are neither technical details nor an exploit publicly available.

Upgrading eliminates this vulnerability.

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Productinfo

Vendor

Name

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.0
VulDB Meta Temp Score: 5.9

VulDB Base Score: 4.5
VulDB Temp Score: 4.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.5
CNA Vector (MITRE): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Recursion
CWE: CWE-674 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: No

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Timelineinfo

05/05/2026 Advisory disclosed
05/05/2026 +0 days CVE reserved
05/05/2026 +0 days VulDB entry created
05/05/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: GHSA-vh5x-56v6-4368
Status: Confirmed

CVE: CVE-2026-44028 (🔒)
GCVE (CVE): GCVE-0-2026-44028
GCVE (VulDB): GCVE-100-361080

Entryinfo

Created: 05/05/2026 07:00
Changes: 05/05/2026 07:00 (62)
Complete: 🔍
Cache ID: 216::103

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