CVE-2026-4602 PUBLISHED

Assigner: snyk
Reserved: 22.03.2026 Published: 23.03.2026 Updated: 23.03.2026

Versions of the package jsrsasign before 11.1.1 are vulnerable to Incorrect Conversion between Numeric Types due to handling negative exponents in ext/jsbn2.js. An attacker can force the computation of incorrect modular inverses and break signature verification by calling modPow with a negative exponent.

Metrics

CVSS 4.0

CVSS Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:P
CVSS Score: 8.7

Exploitability Metrics		Vulnerable System Impact Metrics		Subsequent System Impact Metrics
Attack Vector	Network	Confidentiality	None	Confidentiality	None
Attack Complexity	Low	Integrity	None	Integrity	None
Attack Requirements	None	Availability	High	Availability	None
Privileges Required	None
User Interaction	None

CVSS 4.0

Product Status

Vendor	n/a
Product	jsrsasign
Versions	affected from 0 to 11.1.1 (excl.)

Credits

Kr0emer

References

https://security.snyk.io/vuln/SNYK-JS-JSRSASIGN-15371175
https://gist.github.com/Kr0emer/7ecd2be7d17419e4677315ef3758faf5
https://github.com/kjur/jsrsasign/pull/650
https://github.com/kjur/jsrsasign/commit/5ea1c32bb2aa894b4bd29849839afe4f98728195

Problem Types

Incorrect Conversion between Numeric Types