CVE-2023-45143 Undici's cookie header not cleared on cross-origin redirect in fetch
Undici fails to clear Cookie headers on cross-origin redirects, potentially leaking sensitive cookies to third-party sites or attackers controlling redirect targets.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2023-45143?
CVE-2023-45143 is a low-severity vulnerability in Fedoraproject Fedora, published on 12 Oct 2023. An attacker needs administrator access to exploit it, and only if a user opens a file or follows a link.
Official description
Undici is an HTTP/1.1 client written from scratch for Node.js. Prior to version 5.26.2, Undici already cleared Authorization headers on cross-origin redirects, but did not clear `Cookie` headers. By design, `cookie` headers are forbidden request headers, disallowing them to be set in RequestInit.headers in browser environments. Since undici handles headers more liberally than the spec, there was a disconnect from the assumptions the spec made, and undici's implementation of fetch. As such this may lead to accidental leakage of cookie to a third-party site or a malicious attacker who can control the redirection target (ie. an open redirector) to leak the cookie to the third party site. This was patched in version 5.26.2. There are no known workarounds.
Weakness: CWE-200
Which versions are affected by CVE-2023-45143?
2 open source packages ship an affected version, including undici. It affects 2 products.
| Package | Affected | Fixed in |
|---|---|---|
undici npm | All versions | 5.26.2 |
undici npm | All versions | 5.26.2 |
Products include Fedoraproject Fedora, Nodejs Undici.
How do I fix CVE-2023-45143?
Upgrade undici to 5.26.2 or later.
Is CVE-2023-45143 being exploited?
There is no known exploitation of CVE-2023-45143 in the wild and no public exploit code.
Other vulnerabilities in Fedoraproject Fedora
Sources
Also known as ALPINE-CVE-2023-45143, AZL-31338, CLEANSTART-2026-QW98383, CLEANSTART-2026-TM79261, CLEANSTART-2026-ZI83598, CLSA-2026-1775220180 and 3 more.