Raw vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:HSummary
CVE-2026-27822 is a critical-severity Cross-site Scripting (CWE-79) vulnerability in Rustfs Rustfs. Its CVSS base score is 9.0 (Critical).
Operationally, exploitation aligns with the MITRE ATT&CK technique Browser Session Hijacking (T1185); ranked in the top 10% of CVEs by exploit likelihood; 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 SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — 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-2026-27822 is a Stored Cross-Site Scripting (XSS) vulnerability, classified under CWE-79, affecting the RustFS Console in RustFS, a distributed object storage system built in Rust. The flaw exists in versions prior to 1.0.0-alpha.83, where improper handling allows stored malicious payloads. It has a CVSS v3.1 base score of 9.0 (AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H), indicating critical severity due to high confidentiality, integrity, and availability impacts with changed scope.
An attacker with low privileges (PR:L) can exploit this over the network (AV:N) with low complexity (AC:L) by injecting a payload that bypasses the PDF preview logic in the console. This requires user interaction (UI:R), such as an administrator viewing the malicious content, enabling arbitrary JavaScript execution in the management console's context. The attacker can then steal administrator credentials stored in localStorage, resulting in full account takeover and potential complete system compromise.
The GitHub Security Advisory at https://github.com/rustfs/rustfs/security/advisories/GHSA-v9fg-3cr2-277j details the issue, confirming that upgrading to version 1.0.0-alpha.83 resolves the vulnerability by addressing the PDF preview bypass and XSS handling. Security practitioners should prioritize patching affected RustFS deployments and review console access controls to mitigate risks from privileged users.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-8590
Vulnerability Data
RustFS is a distributed object storage system built in Rust. Prior to version 1.0.0-alpha.83, a Stored Cross-Site Scripting (XSS) vulnerability in the RustFS Console allows an attacker to execute arbitrary JavaScript in the context of the management console. By bypassing…
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the PDF preview logic, an attacker can steal administrator credentials from `localStorage`, leading to full account takeover and system compromise. Version 1.0.0-alpha.83 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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V1.1.2V1.3.2
Mitigating Controls (NIST 800-53 r5) AI
Developer testing and evaluation can discover missing or incorrect input neutralization through targeted web-application tests.
Input validation directly enforces neutralization of untrusted data before it reaches web output generation.
Output filtering can catch or sanitize unneutralized script content before it is served to users.
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.
Secure SDLC practices directly target introduction of XSS via coding standards/testing (mostly), yet the single broad outcome leaves many specific neutralization vectors unaddressed (partial).
Patching and EOL replacement can remediate known XSS instances in libraries or frameworks (partial) but do nothing to enforce input neutralization in application code (none).
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.
Secure-coding testing and automated code-analysis tools are applied to detect improper neutralization of script-related content during web-page generation.
Knowledge exchange on emerging attack techniques and patches reduces the likelihood that cross-site scripting flaws remain unaddressed in deployed applications.
Operational indicators of compromise for web-application attacks can be incorporated into WAF or input-filtering rules, lowering the likelihood that unsanitized data reaches the browser.
Requiring language-specific secure-coding standards and automated scanning during the SDLC catches missing output encoding or improper neutralization of untrusted data before the software reaches production.
Secure-coding standards, SAST scans and removal of insecure code samples together eliminate the failure to neutralize script content that produces cross-site scripting flaws.
Webpage malware scanning and block-listing of known malicious sites reduce the likelihood that reflected or stored script payloads reach a user’s browser.