CVE-2023-46846
Redhat Enterprise Linux Server Tus 8.2 … 9.2
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:NSummary
CVE-2023-46846 is a critical-severity HTTP Request/Response Smuggling (CWE-444) vulnerability in Redhat Enterprise Linux Server Tus. Its CVSS base score is 9.3 (Critical).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 7% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
Squid is vulnerable to HTTP request smuggling due to excessive lenience in its chunked transfer encoding decoder. The flaw, tracked as CVE-2023-46846 and assigned CWE-444, affects the Squid caching proxy and carries a CVSS 3.1 score of 9.3 reflecting network attackability without authentication or user interaction and a scope change that can impact confidentiality and integrity beyond the proxy itself.
A remote attacker can craft ambiguous HTTP/1.1 requests that exploit the decoder behavior to smuggle additional requests or responses. This allows the attacker to bypass intervening firewalls, load balancers, or other frontend security controls and reach origin servers or internal resources that would otherwise be protected.
Red Hat has published multiple errata (RHSA-2023:6266, RHSA-2023:6267, RHSA-2023:6268, RHSA-2023:6748, and RHSA-2023:6801) that address the issue through updated Squid packages. The EPSS score has remained flat at 0.0982 with no material increase since disclosure.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2023-51012
Vulnerability Data
SQUID is vulnerable to HTTP request smuggling, caused by chunked decoder lenience, allows a remote attacker to perform Request/Response smuggling past firewall and frontend security systems.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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V4.1.3V4.2.4V1.5.3V4.1.1
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.
Configuration management can enforce uniform HTTP parsing rules across intermediaries, directly mitigating inconsistent interpretation.
Network monitoring can detect smuggling attempts via anomalous HTTP traffic or logs, while eliminating the inconsistency directly aids detection of such events.
Network protections can enforce consistent HTTP proxy/firewall behavior to block smuggling, and removing the weakness helps prevent unauthorized access via request smuggling.
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.
Security testing can detect HTTP request smuggling vulnerabilities in intermediary components.
Network security controls can enforce consistent HTTP parsing and proxy behavior that mitigates request smuggling.
Secure network services include hardening proxies and gateways against inconsistent HTTP interpretation.
Secure SDLC practices require threat modeling and testing for HTTP parsing inconsistencies in intermediaries.
Application security requirements can mandate strict HTTP message validation and canonicalization.
Secure architecture principles include consistent protocol handling and defense-in-depth for proxies.