Information disclosure in Eclipse Jetty

CVE-2023-26049

Jetty is a java based web server and servlet engine. Nonstandard cookie parsing in Jetty may allow an attacker to smuggle cookies within other cookies, or otherwise perform unintended behavior by tampering with the cookie parsing mechanism. If Jetty sees a cookie VALUE that starts with `"` (double quote), it will continue to read the cookie string until it sees a closing quote -- even if a semicolon is encountered. So, a cookie header such as: `DISPLAY_LANGUAGE="b; JSESSIONID=1337; c=d"` will be parsed as one cookie, with the name DISPLAY_LANGUAGE and a value of b; JSESSIONID=1337; c=d instead of 3 separate cookies. This has security implications because if, say, JSESSIONID is an HttpOnly cookie, and the DISPLAY_LANGUAGE cookie value is rendered on the page, an attacker can smuggle the JSESSIONID cookie into the DISPLAY_LANGUAGE cookie and thereby exfiltrate it. This is significant when an intermediary is enacting some policy based on cookies, so a smuggled cookie can bypass that policy yet still be seen by the Jetty server or its logging system. This issue has been addressed in versions 9.4.51, 10.0.14, 11.0.14, and 12.0.0.beta0 and users are advised to upgrade. There are no known workarounds for this issue.

Vulnerability class: Information Disclosure

EPSS: 0.013 (68.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 2.4 (Low). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:L/I:N/A:N.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2023-26049?
CVE-2023-26049 is a low-severity vulnerability in Eclipse Jetty, classified under Information Disclosure. CVSS score: 2.4/10. Published 2023-04-18.
How severe is CVE-2023-26049?
Low severity. CVSS v3 base score is 2.4 out of 10.
Is CVE-2023-26049 known to be exploited?
9 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.