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

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.4$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.

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: 5.5
VulDB Meta Temp Score: 5.4

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

NVD Base Score: 5.3
NVD Vector: 🔒

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
06/22/2026 +91 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: 06/22/2026 15:44
Changes: 03/23/2026 07:18 (78), 03/23/2026 10:27 (1), 06/22/2026 15:44 (14)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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