Information disclosure in Nodejs Undici

CVE-2023-45143

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.

Vulnerability class: Information Disclosure

EPSS: 0.012 (65.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 3.9 (Low). Vector: CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:L/I:L/A:L.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2023-45143?
CVE-2023-45143 is a low-severity vulnerability in Nodejs Undici, classified under Information Disclosure. CVSS score: 3.9/10. Published 2023-10-12.
How severe is CVE-2023-45143?
Low severity. CVSS v3 base score is 3.9 out of 10.
Is CVE-2023-45143 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.