CVE-2023-26049

Cookie parsing of quoted values can exfiltrate values from other cookies in Eclipse Jetty

Description

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.

Category

2.4
CVSS
Severity: Low
CVSS 3.1 •
EPSS 0.32%
Vendor Advisory github.com
Affected: eclipse jetty.project
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2023-26049?
CVE-2023-26049 has been scored as a low severity vulnerability.
How to fix CVE-2023-26049?
To fix CVE-2023-26049, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2023-26049 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2023-26049 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2023-26049?
CVE-2023-26049 affects eclipse jetty.project.
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