CVE-2023-34036 | Forwarded header exploit with Spring HATEOAS on WebFlux

Reactive web applications that use Spring HATEOAS to produce hypermedia-based responses might be exposed to malicious forwarded headers if they are not behind a trusted proxy that ensures correctness of such headers, or if they don't have anything else in place to handle (and possibly discard) forwarded headers either in WebFlux or at the level of the underlying HTTP server. For the application to be affected, it needs to satisfy the following requirements: * It needs to use the reactive web stack (Spring WebFlux) and Spring HATEOAS to create links in hypermedia-based responses. * The application infrastructure does not guard against clients submitting (X-)Forwarded… headers.

Published: 2023-07-17 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2023-34036 is rated Moderate Risk (42.2/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 0.38%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2023-34036

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-04-11 0.31% 0.38% +0.08%
2 2025-11-21 0.39% 0.31% -0.08%
3 2025-11-18 — 0.39% —

Full EPSS history (9 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-34036

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 1.4 [email protected]
5.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 1.4 [email protected]

Weakness enumeration for CVE-2023-34036

GitHub Security Advisory for CVE-2023-34036

GHSA-7m5c-fgwf-mwph · Severity: medium · Ecosystem: maven — Spring HATEOAS vulnerable to Improper Neutralization of HTTP Headers for Scripting Syntax

Affected software / configurations for CVE-2023-34036

Vendor Product Version Raw CPE
vmware spring_hateoas < 1.5.5 cpe:2.3:a:vmware:spring_hateoas:*:*:*:*:*:*:*:*
vmware spring_hateoas >= 2.0.0, < 2.0.5 cpe:2.3:a:vmware:spring_hateoas:*:*:*:*:*:*:*:*
vmware spring_hateoas 2.1.0 cpe:2.3:a:vmware:spring_hateoas:2.1.0:-:*:*:*:*:*:*
vmware spring_hateoas 2.1.0 cpe:2.3:a:vmware:spring_hateoas:2.1.0:milestone1:*:*:*:*:*:*
vmware spring_hateoas 2.1.0 cpe:2.3:a:vmware:spring_hateoas:2.1.0:rc1:*:*:*:*:*:*

References for CVE-2023-34036

URL Tags
https://spring.io/security/cve-2023-34036 Mitigation Vendor Advisory
cvelogic Threat Intelligence