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Fencer Vulns
medium 5.3

CVE-2026-47845 json

Reactor Netty HTTP Server may incorrectly evaluate proxy addresses

published 2026-08-26 2 mo ago modified 2026-09-04 2 mo ago also EUVD-2026-66819

cvss
5.3
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.3%
EPSS 0.3% chance of exploitation in 30 days, percentile 22%
public exploits
0
none known

Summary

In specific scenarios, Reactor Netty HTTP Server may incorrectly evaluate the remote IP address when HAProxy Protocol is enabled. In order for this to happen, the application must be configured to use HAProxy Protocol. Reactor Netty 1.3.0 - 1.3.6 Reactor Netty 1.1.0 - 1.2.18 Reactor Netty 1.0.52 and earlier

Patch / fix

  • broadcom reactor_netty 1.0.53, 1.2.19, 1.3.6.1

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-2026-47845 updated cvss 5.3

io.projectreactor.netty/reactor-netty: Reactor Netty HTTP Server: Information disclosure via incorrect HAProxy Protocol evaluation

  • Red Hat Fuse 7 reactor-netty 0.9.25.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

Exploit prediction

0.29% chance of exploitation in the next 30 days, higher than 22% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Affected products

  • Spring Reactor Netty

Classification

Weakness
  • CWE-290 Authentication Bypass by Spoofing

References

Sources

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.