Spring Framework sameSite Attribute Dropped in JettyCoreServerHttpResponse

published 2026-08-27 2 mo ago modified 2026-09-10 59 d ago also EUVD-2026-66857

cvss: 7.5; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.4%; EPSS 0.4% chance of exploitation in 30 days, percentile 37%
public exploits: 0; none known

A WebFlux application running on the Jetty 12 Core reactive adapter serializes response cookies without the sameSite attribute. Spring Framework 7.0.0 - 7.0.8 Spring Framework 6.2.0 - 6.2.19

Patch / fix

fixed in 1

vmware spring_framework 6.2.20, 7.0.8.1

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-47889 updated 2026-11-07 cvss 5.4

org.springframework/spring-webflux: org.eclipse.jetty/jetty-core: Spring Framework: Missing SameSite attribute in WebFlux cookies on Jetty 12

Red Hat AMQ Broker 7 jetty-core 12.1.10.redhat-00001 Red Hat build of Apache Camel for Spring Boot 4 jetty-core 12.1.10.redhat-00001
affected: no fix available
Red Hat Fuse 7 spring-webflux 5.2.13.RELEASE
affected: no fix planned “Out of support scope”

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation: none
Automatable: yes
Technical impact: partial
Assessed: 2 mo ago (2026-08-27)

Exploit prediction

0.43% chance of exploitation in the next 30 days, higher than 37% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CISA ADP	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
CNA	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Affected products

Spring Spring Framework

Classification

Weakness

CWE-1275 Sensitive Cookie with Improper SameSite Attribute

Technology feeds

Spring rss critical rss

References

spring.io /security/cve-2026-47889
vendor-advisory

Sources

CVE List CVE-2026-47889
NVD CVE-2026-47889

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary