# CVE-2023-46218: Security feature bypass in curl

> A malicious server can bypass cookie domain restrictions in curl, allowing cookies to be sent to unrelated domains and potentially exposing sensitive data.

- **Severity:** Medium 6.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 7 Dec 2023
- **Updated:** 15 Oct 2026
- **Also known as:** ALPINE-CVE-2023-46218, ALSA-2024:1129, AZL-32099, AZL-32119, AZL-32126, AZL-34618, AZL-35019, BELL-CVE-2023-46218, CLEANSTART-2026-BQ84049, CLSA-2024-1710436611, CLSA-2024-1710786562, CLSA-2024-1712672068, CLSA-2024-1716882786, CLSA-2024-1716883173, CURL-CVE-2023-46218, DEBIAN-CVE-2023-46218, DSA-5587-1, GHSA-59mm-6rr4-j9p2, JLSEC-2026-411, OESA-2023-1913, RHSA-2024:0434, RHSA-2024:0452, RHSA-2024:1129, SUSE-SU-2023:4713-1, UBUNTU-CVE-2023-46218, USN-6641-1

## What is CVE-2023-46218?

CVE-2023-46218 is a medium-severity vulnerability in Fedoraproject Fedora, published on 7 Dec 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

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.

Weakness: CWE-178 (Improper Handling of Case Sensitivity)

## Which versions are affected by CVE-2023-46218?

It affects 2 products.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `curl` | AlmaLinux:9 | All versions | 7.76.1-26.el9_3.3 |
| `curl-minimal` | AlmaLinux:9 | All versions | 7.76.1-26.el9_3.3 |
| `libcurl` | AlmaLinux:9 | All versions | 7.76.1-26.el9_3.3 |
| `libcurl-devel` | AlmaLinux:9 | All versions | 7.76.1-26.el9_3.3 |
| `libcurl-minimal` | AlmaLinux:9 | All versions | 7.76.1-26.el9_3.3 |
| `curl-debuginfo` | Red Hat:enterprise_linux:9::appstream | All versions | 0:7.76.1-26.el9_3.3 |
| `curl-debugsource` | Red Hat:enterprise_linux:9::appstream | All versions | 0:7.76.1-26.el9_3.3 |
| `curl-minimal-debuginfo` | Red Hat:enterprise_linux:9::appstream | All versions | 0:7.76.1-26.el9_3.3 |
| `libcurl-debuginfo` | Red Hat:enterprise_linux:9::appstream | All versions | 0:7.76.1-26.el9_3.3 |
| `libcurl-devel` | Red Hat:enterprise_linux:9::appstream | All versions | 0:7.76.1-26.el9_3.3 |
| `libcurl-minimal-debuginfo` | Red Hat:enterprise_linux:9::appstream | All versions | 0:7.76.1-26.el9_3.3 |
| `curl` | Red Hat:enterprise_linux:9::baseos | All versions | 0:7.76.1-26.el9_3.3 |
| `curl-debuginfo` | Red Hat:enterprise_linux:9::baseos | All versions | 0:7.76.1-26.el9_3.3 |
| `curl-debugsource` | Red Hat:enterprise_linux:9::baseos | All versions | 0:7.76.1-26.el9_3.3 |
| `curl-minimal` | Red Hat:enterprise_linux:9::baseos | All versions | 0:7.76.1-26.el9_3.3 |
| `curl-minimal-debuginfo` | Red Hat:enterprise_linux:9::baseos | All versions | 0:7.76.1-26.el9_3.3 |
| `libcurl` | Red Hat:enterprise_linux:9::baseos | All versions | 0:7.76.1-26.el9_3.3 |
| `libcurl-debuginfo` | Red Hat:enterprise_linux:9::baseos | All versions | 0:7.76.1-26.el9_3.3 |
| `libcurl-minimal` | Red Hat:enterprise_linux:9::baseos | All versions | 0:7.76.1-26.el9_3.3 |
| `libcurl-minimal-debuginfo` | Red Hat:enterprise_linux:9::baseos | All versions | 0:7.76.1-26.el9_3.3 |
| `curl-debuginfo` | Red Hat:rhel_eus:9.0::appstream | All versions | 0:7.76.1-14.el9_0.11 |
| `curl-debugsource` | Red Hat:rhel_eus:9.0::appstream | All versions | 0:7.76.1-14.el9_0.11 |
| `curl-minimal-debuginfo` | Red Hat:rhel_eus:9.0::appstream | All versions | 0:7.76.1-14.el9_0.11 |
| `libcurl-debuginfo` | Red Hat:rhel_eus:9.0::appstream | All versions | 0:7.76.1-14.el9_0.11 |
| `libcurl-devel` | Red Hat:rhel_eus:9.0::appstream | All versions | 0:7.76.1-14.el9_0.11 |
| `libcurl-minimal-debuginfo` | Red Hat:rhel_eus:9.0::appstream | All versions | 0:7.76.1-14.el9_0.11 |
| `curl` | Red Hat:rhel_eus:9.0::baseos | All versions | 0:7.76.1-14.el9_0.11 |
| `curl-debuginfo` | Red Hat:rhel_eus:9.0::baseos | All versions | 0:7.76.1-14.el9_0.11 |
| `curl-debugsource` | Red Hat:rhel_eus:9.0::baseos | All versions | 0:7.76.1-14.el9_0.11 |
| `curl-minimal` | Red Hat:rhel_eus:9.0::baseos | All versions | 0:7.76.1-14.el9_0.11 |
| `curl-minimal-debuginfo` | Red Hat:rhel_eus:9.0::baseos | All versions | 0:7.76.1-14.el9_0.11 |
| `libcurl` | Red Hat:rhel_eus:9.0::baseos | All versions | 0:7.76.1-14.el9_0.11 |
| `libcurl-debuginfo` | Red Hat:rhel_eus:9.0::baseos | All versions | 0:7.76.1-14.el9_0.11 |
| `libcurl-minimal` | Red Hat:rhel_eus:9.0::baseos | All versions | 0:7.76.1-14.el9_0.11 |
| `libcurl-minimal-debuginfo` | Red Hat:rhel_eus:9.0::baseos | All versions | 0:7.76.1-14.el9_0.11 |
| `curl-debuginfo` | Red Hat:rhel_eus:9.2::appstream | All versions | 0:7.76.1-23.el9_2.6 |
| `curl-debugsource` | Red Hat:rhel_eus:9.2::appstream | All versions | 0:7.76.1-23.el9_2.6 |
| `curl-minimal-debuginfo` | Red Hat:rhel_eus:9.2::appstream | All versions | 0:7.76.1-23.el9_2.6 |
| `libcurl-debuginfo` | Red Hat:rhel_eus:9.2::appstream | All versions | 0:7.76.1-23.el9_2.6 |
| `libcurl-devel` | Red Hat:rhel_eus:9.2::appstream | All versions | 0:7.76.1-23.el9_2.6 |

Products: Fedoraproject Fedora, Haxx Curl.

## How do I fix CVE-2023-46218?

Upgrade to a fixed version.

## Is CVE-2023-46218 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2023-46218 exists.

## Other vulnerabilities in Fedoraproject Fedora

- [CVE-2024-4577](https://insights.sbomify.com/CVE-2024-4577/): PHP-CGI OS Command Injection (critical 9.8, exploited in the wild)
- [CVE-2021-39226](https://insights.sbomify.com/CVE-2021-39226/): Grafana Authentication Bypass (critical 9.8, exploited in the wild)
- [CVE-2019-5544](https://insights.sbomify.com/CVE-2019-5544/): VMware ESXi and Horizon DaaS OpenSLP Heap-Based Buffer Overflow (critical 9.8, exploited in the wild)
- [CVE-2024-4947](https://insights.sbomify.com/CVE-2024-4947/): Google Chromium V8 Type Confusion (critical 9.6, exploited in the wild)
- [CVE-2024-4671](https://insights.sbomify.com/CVE-2024-4671/): Google Chromium Visuals Use-After-Free (critical 9.6, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-46218 and fix it if it is affected.

What it is: CVE-2023-46218 is a medium-severity vulnerability in Fedoraproject Fedora, published on 7 Dec 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2023-46218 exists.

Affected product: Fedoraproject Fedora. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2023-46218/ (Markdown: https://insights.sbomify.com/CVE-2023-46218/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-46218
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-46218
- OSV: https://osv.dev/vulnerability/CVE-2023-46218

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-46218/
Summaries are generated and may contain mistakes; the official description above is the record.