Rhino vulnerable high CPU usage and potential DoS when passing specific numbers to toFixed() function

published 2025-12-03 11 mo ago modified 2026-10-18 21 d ago also GHSA-3w8q-xq97-5j7x , EUVD-2025-201013

cvss: 7.5; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 21%
public exploits: 0; none known

Rhino is an open-source implementation of JavaScript written entirely in Java. Prior to 1.8.1, 1.7.15.1, and 1.7.14.1, when an application passed an attacker controlled float poing number into the toFixed() function, it might lead to high CPU consumption and a potential Denial of Service. Small numbers go through this call stack: NativeNumber.numTo > DToA.JS_dtostr > DToA.JS_dtoa > DToA.pow5mult where pow5mult attempts to raise 5 to a ridiculous power. This vulnerability is fixed in 1.8.1, 1.7.15.1, and 1.7.14.1.

Patch / fix

fixed in 2 distros 4 links 1

maven org.mozilla:rhino 1.7.14.1, 1.7.15.1, 1.8.1
mozilla rhino 1.7.14.1

debian suse opensuse azure linux

rhino Debian 12 1.7.14.1-0+deb12u1
rhino Debian 13 1.7.15.1-0.1~deb13u1
rhino Debian 14 1.7.15.1-0.1

debian advisories DEBIAN-CVE-2025-66453

rhino SLES for SAP applications 16.0, SLES 16.0 1.7.15.1-160000.1.1
rhino SLE Module for Basesystem 15 SP7, SLE Module for Basesystem 15 SP6, openSUSE Leap 15.6 1.7.15.1-150200.12.7.1

suse advisories SUSE-SU-2026:20603-1 SUSE-SU-2025:4390-1

rhino openSUSE Leap 16.0 1.7.15.1-160000.1.1
rhino openSUSE Tumbleweed 1.7.15.1-1.1

opensuse advisories openSUSE-SU-2026:20297-1 openSUSE-SU-2025:15798-1

rhino Azure Linux 3.0 1.7.15.1-1

azure linux advisories AZL-71221

Azure Linux vulnerability data, Copyright (c) Microsoft Corporation, from https://github.com/microsoft/AzureLinuxVulnerabilityData via OSV, under the MIT licence; changed: normalised to fixed package versions per release. MIT

github.com/mozilla/rhino@2bcf4c4 commit

CISA SSVC

Exploitation: none
Automatable: yes
Technical impact: partial
Assessed: 11 mo ago (2025-12-03)

Exploit prediction

0.29% chance of exploitation in the next 30 days, higher than 21% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	4.0	5.5	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P
CNA	4.0	5.5	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
NVD	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected packages

ecosystem	package	affected	fixed in
maven	org.mozilla:rhino	<1.7.14.1 >=1.7.15, <1.7.15.1 >=1.8.0, <1.8.1	1.7.14.1 1.7.15.1 1.8.1

Affected products

mozilla rhino

Classification

Weakness

CWE-400 Uncontrolled Resource Consumption

References

github.com /mozilla/rhino/commit/2bcf4c43deace35f1f57d86377c6767b0608986e
web
github.com /mozilla/rhino/security/advisories/GHSA-3w8q-xq97-5j7x
web, vendor-advisory
nvd.nist.gov /vuln/detail/CVE-2025-66453
advisory
github.com /mozilla/rhino
package

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.

Summary