jsrsasign up to 11.1.0 KEYUTIL Parser ext/rsa.js divide by zero

CVSS Meta Temp Score
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CTI Interest Score
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5.5$0-$5k0.00

Summaryinfo

A vulnerability marked as problematic has been reported in jsrsasign up to 11.1.0. Impacted is an unknown function of the file ext/rsa.js of the component KEYUTIL Parser. This manipulation causes divide by zero. The identification of this vulnerability is CVE-2026-4603. The attack can only be executed locally. There is no exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability has been found in jsrsasign up to 11.1.0 and classified as problematic. Affected by this vulnerability is an unknown code of the file ext/rsa.js of the component KEYUTIL Parser. The manipulation with an unknown input leads to a divide by zero vulnerability. The CWE definition for the vulnerability is CWE-369. The product divides a value by zero. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

Versions of the package jsrsasign before 11.1.1 are vulnerable to Division by zero due to the RSASetPublic/KEYUTIL parsing path in ext/rsa.js and the BigInteger.modPowInt reduction logic in ext/jsbn.js. An attacker can force RSA public-key operations (e.g., verify and encryption) to collapse to deterministic zero outputs and hide “invalid key” errors by supplying a JWK whose modulus decodes to zero.

The advisory is shared at security.snyk.io. This vulnerability is known as CVE-2026-4603 since 03/22/2026. The exploitation appears to be easy. An attack has to be approached locally. Technical details are known, but no exploit is available.

It is declared as proof-of-concept.

Upgrading to version 11.1.1 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-14380). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 5.6
VulDB Meta Temp Score: 5.5

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 5.9
CNA Vector (snyk): 🔒

CVSSv2info

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Divide by zero
CWE: CWE-369 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: No

Availability: 🔒
Status: Proof-of-Concept

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: jsrsasign 11.1.1

Timelineinfo

03/22/2026 CVE reserved
03/23/2026 +1 days Advisory disclosed
03/23/2026 +0 days VulDB entry created
03/23/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: SNYK-JS-JSRSASIGN-15371176
Status: Confirmed

CVE: CVE-2026-4603 (🔒)
GCVE (CVE): GCVE-0-2026-4603
GCVE (VulDB): GCVE-100-352489
EUVD: 🔒

Entryinfo

Created: 03/23/2026 07:18
Updated: 03/23/2026 10:27
Changes: 03/23/2026 07:18 (78), 03/23/2026 10:27 (1)
Complete: 🔍
Cache ID: 216:2DB:103

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