CVE-2023-46218

Haxx Curl 7.46.0 – 8.4.0

Public PoC

Published

07 December 2023

Modified

12 May 2026

Patch / advisory

View advisory

CVSS Score v3.1 6.5

Click a component to see what it means

Raw vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

EPSS Score 0.017 77th percentile

Risk Priority 54 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2023-46218 is a medium-severity Improper Handling of Case Sensitivity (CWE-178) vulnerability in Haxx Curl. Its CVSS base score is 6.5 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Data Obfuscation (T1001); ranked in the top 23% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

🇪🇺 ENISA EUVD: EUVD-2023-50460

Vulnerability Data

This flaw allows a malicious HTTP server to set "super cookies" in curl that are then passed back to more origins than what is otherwise allowed or possible. This allows a site to set cookies that then would get sent…

to different and unrelated sites and domains. It could do this by exploiting a mixed case flaw in curl's function that verifies a given cookie domain against the Public Suffix List (PSL). For example a cookie could be set with `domain=co.UK` when the URL used a lower case hostname `curl.co.uk`, even though `co.uk` is listed as a PSL domain.

CWE(s): NVD-CWE-noinfo CWE-178

Related Threats

MITRE ATT&CK Enterprise Techniques

T1001 Data Obfuscation Command And Control

Adversaries may obfuscate command and control traffic to make it more difficult to detect.

attack.mitre.org →

T1003.001 LSASS Memory Credential Access

Adversaries may attempt to access credential material stored in the process memory of the Local Security Authority Subsystem Service (LSASS).

attack.mitre.org →

T1003.006 DCSync Credential Access

Adversaries may attempt to access credentials and other sensitive information by abusing a Windows Domain Controller's application programming interface (API)(Citation: Microsoft DRSR Dec 2017) (Citation: Microsoft GetNCCChanges) (Citati…

attack.mitre.org →

T1010 Application Window Discovery Discovery

Adversaries may attempt to get a listing of open application windows.

attack.mitre.org →

T1011 Exfiltration Over Other Network Medium Exfiltration

Adversaries may attempt to exfiltrate data over a different network medium than the command and control channel.

attack.mitre.org →

T1016.001 Internet Connection Discovery Discovery

Adversaries may check for Internet connectivity on compromised systems.

attack.mitre.org →

Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-46219Same product: Fedoraproject Fedora

CVE-2025-50864Shared CWE-178

CVE-2024-38820Shared CWE-178

CVE-2026-89012Shared CWE-178

CVE-2026-100693Shared CWE-178

CVE-2026-3833Shared CWE-178

CVE-2026-40453Shared CWE-178

CVE-2026-100541Shared CWE-178

CVE-2026-82067Shared CWE-178

CVE-2023-3545Shared CWE-178

Affected Assets

haxx

curl

7.46.0 — 8.4.0

fedoraproject

fedora

Mitigating Controls

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.

PR.PS-06 partial match

blocks

Secure SDLC practices can catch and prevent case-sensitivity flaws during code review or testing, but fixing one CWE achieves negligible coverage of the broad control.

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.

A.8.19 Installation of software on operational systems partial match

removes

A.8.25 Secure development life cycle partial match

blocks

Secure SDLC practices should include case-sensitivity requirements in design and coding standards.

A.8.26 Application security requirements partial match

blocks

Application security requirements must specify case handling for identifiers and paths.

A.8.27 Secure system architecture and engineering principles partial match

blocks

Architecture principles should enforce canonical, case-aware resource naming.

A.8.28 Secure coding partial match