CVE-2026-44592 | Gradient: Unauthenticated worker on /proto → arbitrary NAR write / cache poisoning

Gradient is a nix-based continuous integration system. In 1.1.0, when GRADIENT_DISCOVERABLE=true (the default, and the NixOS module default), anyone who can reach /proto can register as a worker without any credentials by sending a fresh, never-registered worker UUID. The resulting session has PeerAuth::Open, i.e. it sees jobs from every organisation, and can immediately NarPush/NarUploaded arbitrary store paths into nar_storage and the cached_path table. This vulnerability is fixed in 1.1.1.

Published: 2026-05-14 Last update: 2026-05-15 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-44592 is rated Low Risk (39.1/100): CVSS Critical severity, with low exploitation likelihood (EPSS 0.02%). Mandatory action: 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-2026-44592

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 2026-05-15 0.02%

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-44592

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.4 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
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:N)
No account or special rights needed—anonymous or random user is enough.
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:L)
Some sensitive info could get out, but not a total data dump.
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.
3.9 5.5 [email protected]

Weakness enumeration for CVE-2026-44592

Affected software / configurations for CVE-2026-44592

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2026-44592

cvelogic Threat Intelligence