Raw vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:P/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:XSummary
CVE-2026-22043 is a medium-severity Improper Privilege Management (CWE-269) vulnerability in Rustfs Rustfs. Its CVSS base score is 5.7 (Medium).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 32th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
The strongest mitigations our analysis identified map to AC-2 (Account Management) and AC-24 (Access Control Decisions) — see the control section below for these in your framework.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
CVE-2026-22043 affects RustFS, a distributed object storage system built in Rust, specifically versions 1.0.0-alpha.13 through 1.0.0-alpha.78. The vulnerability stems from a flawed `deny_only` short-circuit in the RustFS IAM (Identity and Access Management) component, which permits a restricted service account or STS (Security Token Service) credential to self-issue an unrestricted service account. This results in the new credential inheriting the parent's full privileges, enabling privilege escalation and the bypass of session or inline policy restrictions. The issue is rated with a CVSS v3.1 base score of 9.8 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H) and is associated with CWEs 269 (Improper Privilege Management), 284 (Improper Access Control), and 522 (Insufficiently Protected Credentials).
Attackers with access to any restricted service account or valid STS credential can exploit this vulnerability remotely over the network with low complexity and no special privileges or user interaction required. By leveraging the flawed short-circuit, they can generate a new unrestricted service account that inherits the full privileges of the parent account, achieving complete privilege escalation. This grants high-impact unauthorized access to confidentiality, integrity, and availability across the RustFS deployment, potentially allowing full system compromise depending on the parent's permissions.
The GitHub Security Advisory (GHSA-xgr5-qc6w-vcg9) confirms that RustFS version 1.0.0-alpha.79 addresses the issue by fixing the `deny_only` short-circuit logic in the IAM component. Security practitioners should upgrade to this version or later and review IAM policies for restricted accounts to mitigate exposure, as no workarounds are detailed in available references.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-1471
Vulnerability Data
RustFS is a distributed object storage system built in Rust. In versions 1.0.0-alpha.13 through 1.0.0-alpha.78, a flawed `deny_only` short-circuit in RustFS IAM allows a restricted service account or STS credential to self-issue an unrestricted service account, inheriting the parent’s full…
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privileges. This enables privilege escalation and bypass of session/inline policy restrictions. Version 1.0.0-alpha.79 fixes the issue.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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- 14 hardening rules · 10 OS baselines
V10.3.5V11.3.3
Mitigating Controls (NIST 800-53 r5) AI
Directly enforces approved authorizations for logical access, stopping unauthorized actors from reaching resources.
Protection of information at rest requires encryption or equivalent safeguards for stored credentials.
Transmission confidentiality and integrity enforcement stops credentials from being sent in plaintext or without protection.
Account management directly governs assignment and tracking of privileges so proper implementation stops the weakness from being introduced.
Requiring explicit access-control decisions ensures privileges are evaluated rather than assumed or omitted.
Enforces flow-control policies that restrict information movement between subjects and objects.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Encrypting data-at-rest fully prevents insecure credential storage while only partially satisfying the broader data-protection outcome.
Encrypting data-in-transit fully prevents interception of credentials in motion while only partially satisfying the broader data-protection outcome.
Credential management practices directly reduce insecure storage/transmission but do not guarantee encryption or transport protection.
Protecting identity assertions covers conveyance of credentials but is narrower than full credential lifecycle protection.
PR.AA-05 enforces least privilege/SoD and periodic reviews that directly remove most privilege-assignment defects, yet CWE-269 also covers escalation paths and role design outside a single access-management control.
Hardened baselines and deviation monitoring directly eliminate most configuration-induced access-control defects, yet CWE-284 also encompasses code-level and design flaws outside the scope of configuration management alone.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Defining and enforcing explicit access rights and restrictions for each entity directly stops the assignment of permissions that exceed what is required, eliminating the root condition that allows improper access control.
Formal authorization, role-based provisioning, and timely revocation of access rights directly stop the creation of accounts or permissions that exceed what the business actually needs.
By enforcing explicit rules on which identities or groups may perform read, write, delete or execute operations and by denying anonymous access to sensitive data, the control directly stops the creation of overly permissive or missing access-control checks.
Requiring one-to-one mapping of identities to entities and timely removal of unused identities directly stops attackers from leveraging stale or shared accounts to bypass access restrictions.
Requiring protected storage, transmission, and non-display of passwords prevents credentials from being stored or sent in clear text where they can be harvested by unauthorized actors.
By explicitly transferring security roles and responsibilities when personnel change jobs or leave, the control reduces the chance that former employees retain access rights they no longer need, thereby limiting improper access control.
Hardening callouts derived
Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).
Oracle Linux 8 (2 rules)
- V-248597 There must be no "shosts.equiv" files on the OL 8 operating system. prevents CWE-284
- V-248598 There must be no ".shosts" files on the OL 8 operating system. prevents CWE-284
Oracle Linux 9 (2 rules)
- V-271758 OL 9 file systems must not contain .shosts files. prevents CWE-284
- V-271757 OL 9 file systems must not contain shosts.equiv files. prevents CWE-284
RHEL 7 (2 rules)
- V-204606 The Red Hat Enterprise Linux operating system must not contain .shosts files. prevents CWE-284
- V-204607 The Red Hat Enterprise Linux operating system must not contain shosts.equiv files. prevents CWE-284
RHEL 8 (2 rules)
- V-230283 There must be no shosts.equiv files on the RHEL 8 operating system. prevents CWE-284
- V-230284 There must be no .shosts files on the RHEL 8 operating system. prevents CWE-284
Windows 10 (1 rule)
- V-220712 Only accounts responsible for the administration of a system must have Administrator rights on the system. prevents CWE-269
Windows 11 (1 rule)
- V-253269 Only accounts responsible for the administration of a system must have Administrator rights on the system. prevents CWE-269
Windows Server 2016 (1 rule)
- V-225007 Only administrators responsible for the member server or standalone or nondomain-joined system must have Administrator rights on the system. prevents CWE-269
Windows Server 2019 (1 rule)
- V-205746 Windows Server 2019 must only allow Administrators responsible for the member server or standalone or nondomain-joined system to have Administrator rights on the system. prevents CWE-269
Windows Server 2022 (1 rule)
- V-254428 Windows Server 2022 must only allow administrators responsible for the member server or standalone or nondomain-joined system to have Administrator rights on the system. prevents CWE-269