PT-2026-27054 · Jsrsasign · Jsrsasign

Kr0Emer · Published 2026-03-23 · Updated 2026-03-23 · CVE-2026-4598

Positive Technologies (AI Summary)

CVSS v4.0

7.7

High

Base vector

AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/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

Name of the Vulnerable Software and Affected Versions jsrsasign versions prior to 11.1.1

Description The jsrsasign package contains a flaw where the bnModInverse function within the ext/jsbn2.js file can enter an infinite loop. This occurs when the BigInteger.modInverse implementation receives zero or negative inputs, potentially causing a denial-of-service condition by hanging the process. The vulnerable function is modInverse(). The issue can be triggered by supplying crafted values such as modInverse(0, m) or modInverse(-1, m).

Recommendations Update to jsrsasign version 11.1.1 or later.

Exploit

Fix

Infinite Loop

Weakness Enumeration

CWE-835

Related Identifiers

CVE-2026-4598

GHSA-8G7P-JF3G-GXCP

Affected Products

Jsrsasign

References · 11

• 🔥 https://gist.github.com/Kr0emer/a1bf5cd4547cc630d2dcc5e761de8264 · Exploit
• https://github.com/kjur/jsrsasign/commit/ca5b027240287a1e71fe63019fc4400332594323 · Patch
• https://osv.dev/vulnerability/GHSA-8g7p-jf3g-gxcp · Vendor Advisory
• https://osv.dev/vulnerability/CVE-2026-4598 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-4598 · Security Note
• https://github.com/kjur/jsrsasign · Note
• https://github.com/kjur/jsrsasign/pull/648 · Note
• https://security.snyk.io/vuln/SNYK-JS-JSRSASIGN-15370938 · Note
• https://twitter.com/CVEnew/status/2035992478516457790 · Twitter Post
• https://twitter.com/CVEarity/status/2036120505443557655 · Twitter Post
• https://twitter.com/VulmonFeeds/status/2035983706645573683 · Twitter Post