CVE-2023-42457 | plone.rest vulnerable to Denial of Service when ++api++ is used many times

plone.rest allows users to use HTTP verbs such as GET, POST, PUT, DELETE, etc. in Plone. Starting in the 2.x branch and prior to versions 2.0.1 and 3.0.1, when the `++api++` traverser is accidentally used multiple times in a url, handling it takes increasingly longer, making the server less responsive. Patches are available in `plone.rest` 2.0.1 and 3.0.1. Series 1.x is not affected. As a workaround, one may redirect `/++api++/++api++` to `/++api++` in one's frontend web server (nginx, Apache).

Published: 2023-09-21 Last update: 2025-02-13 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2023-42457 is rated Moderate Risk (45.7/100): CVSS High severity, with low exploitation likelihood (EPSS 0.23%). 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-2023-42457

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 2025-11-21 0.65% 0.23% -0.42%
2 2025-11-18 0.17% 0.65% +0.48%
3 2025-04-15 — 0.17% —

Full EPSS history (8 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-42457

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H 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:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 [email protected]
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H 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:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 [email protected]

Weakness enumeration for CVE-2023-42457

GitHub Security Advisory for CVE-2023-42457

GHSA-h6rp-mprm-xgcq · Severity: medium · Ecosystem: pip — plone.rest vulnerable to Denial of Service when ++api++ is used many times

Affected software / configurations for CVE-2023-42457

Vendor Product Version Raw CPE
plone rest 2.0.0 cpe:2.3:a:plone:rest:2.0.0:*:*:*:*:*:*:*
plone rest 3.0.0 cpe:2.3:a:plone:rest:3.0.0:*:*:*:*:*:*:*

References for CVE-2023-42457

cvelogic Threat Intelligence