RustFS: Hard-coded RSA private key in license verifier permits arbitrary license forgery

published 2026-05-28 5 mo ago modified 2026-06-17 4 mo ago also EUVD-2026-32996

cvss: 8.7; version 4.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.2%; EPSS 0.2% chance of exploitation in 30 days, percentile 15%
public exploits: 0; none known

RustFS is a distributed object storage system built in Rust. Prior to 1.0.0-beta.2, crates/appauth/src/token.rs ships a 2048-bit RSA private key as a string constant named TEST_PRIVATE_KEY and uses it in production via parse_license() to "verify" license tokens. Because the key is embedded in every published source release and binary, anyone who can read the repository or extract it from the binary can mint arbitrary license tokens (any subject, any expiration). When the license Cargo feature is enabled, this defeats the entire license-enforcement mechanism. This vulnerability is fixed in 1.0.0-beta.2.

Patch / fix

fixed in 1

rustfs rustfs 1.0.0-beta.2

CISA SSVC

Exploitation: Proof of concept is public
Automatable: yes
Technical impact: partial
Assessed: 5 mo ago (2026-05-29)

Exploit prediction

0.24% chance of exploitation in the next 30 days, higher than 15% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

github.com https://github.com/rustfs/rustfs/security/advisories/GHSA-923g-jp7v-f97f referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	4.0	8.7	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
CNA	4.0	8.7	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affected products

rustfs rustfs

Classification

Weakness

CWE-321 Use of Hard-coded Cryptographic Key

References

github.com /rustfs/rustfs/security/advisories/GHSA-923g-jp7v-f97f
exploit

Sources

CVE List CVE-2026-45041
NVD CVE-2026-45041

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.

Summary