CVE
CVE-2026-4602
jsrsasign: Negative Exponent Handling Leads to Signature Verification Bypass
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.
Package Versions Affected
Package Version
patch Availability
No items found.
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CVSS Version
Severity
Base Score
CVSS Version
Score Vector
C
H
U
7.7
-
4.0
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/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
C
H
U
0
-
3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
C
H
U
7.5
-
3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Related Resources
No items found.
References
https://nvd.nist.gov/vuln/detail/CVE-2026-4602, https://github.com/kjur/jsrsasign/pull/650, https://github.com/kjur/jsrsasign/commit/5ea1c32bb2aa894b4bd29849839afe4f98728195, https://gist.github.com/Kr0emer/7ecd2be7d17419e4677315ef3758faf5, https://github.com/kjur/jsrsasign, https://security.snyk.io/vuln/SNYK-JS-JSRSASIGN-15371175
Basic Information
Ecosystem
