Eclipse Jetty's cookie parsing of quoted values can exfiltrate values from other cookies

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

2.4 · CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:L/I:N/A:N

EPSS

• CVE-2023-26049: 1.30% estimated exploitation activity in the next 30 days; percentile 70.47 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

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: DISPLAYLANGUAGE="b; JSESSIONID=1337; c=d" will be parsed as one cookie, with the name DISPLAYLANGUAGE and a value of b; JSESSIONID=1337; c=d instead of 3 separate cookies. Impact This has security implications because if, say, JSESSIONID is an HttpOnly cookie, and the DISPLAYLANGUAGE cookie value is rendered on the page, an attacker can smuggle the JSESSIONID cookie into the DISPLAYLANGUAGE 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. Patches…

Published by the source

18 Apr 2023, 22:19 UTC

Last modified by the source

6 Nov 2023, 05:01 UTC

Source last checked

26 Oct 2026, 16:16 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-p26g-97m4-6q7c

Preview the exact text before you copy it. Commands are read-only suggestions; review them before running anything.

# Patch Next advisory brief: CVE-2023-26049

Advisory: Eclipse Jetty's cookie parsing of quoted values can exfiltrate values from other cookies
IDs: CVE-2023-26049, GHSA-p26g-97m4-6q7c
Record: https://patchnext.com/advisories/cve-2023-26049 (revision 1, source checked 26 Oct 2026, 16:16 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Low (CVSS 2.4)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: org.eclipse.jetty:jetty-server 12.0.0.beta0, 11.0.14, 10.0.14, 9.4.51.v20230217. A vendor fix does not mean a deployment is fixed.

## Affected components
- Maven org.eclipse.jetty:jetty-server: affected >= 10.0.0, < 10.0.14; >= 11.0.0, < 11.0.14; >= 12.0.0alpha0, < 12.0.0.beta0; < 9.4.51.v20230217; fixed in 11.0.14, 12.0.0.beta0, 9.4.51.v20230217, 10.0.14

## Suggested inspection (read-only)
- Maven org.eclipse.jetty:jetty-server: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on org.eclipse.jetty:jetty-server.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-p26g-97m4-6q7c (GitHub-reviewed advisory GHSA-p26g-97m4-6q7c lists affected ranges: Maven org.eclipse.jetty:jetty-server >=10.0.0 =11.0.0 =12.0.0alpha0 =0 <9.4.51.v20230217)

Commands are suggestions: review each one before running it.