CyberSecBulletin
CVE-2026-4598NVD status: Modified

jsrsasign: Loop with Unreachable Exit Condition

CVE-2026-4598 is a high-severity loop with unreachable exit condition vulnerability in jsrsasign, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version 11.1.1 as the first without the flaw, so updating jsrsasign to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.57% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update jsrsasign to 11.1.1 or a later version.
  2. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
Jsrsasignjsrsasignbefore 11.1.111.1.1
Org.webjars.npm:jsrsasignorg.webjars.npm:jsrsasignall versionsNot stated
Red HatMigration Toolkit for Virtualization 2.1Not specified in the recordNot stated
Red HatMigration Toolkit for Virtualization 2.9Not specified in the recordNot stated
Red HatRed Hat Quay 3.10Not specified in the recordNot stated
Red HatRed Hat Quay 3.12Not specified in the recordNot stated
Red HatRed Hat Quay 3.15Not specified in the recordNot stated
Red HatRed Hat Quay 3.16Not specified in the recordNot stated
Red HatRed Hat Quay 3.9Not specified in the recordNot stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
NoneNo data is disclosed.
Integrity
NoneNothing can be modified.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. Scored by CNA (snyk.io).

Scoring systemScoreSeverityScored by
CVSS 4.07.7HighCNA (snyk.io)
CVSS 3.17.5HighCNA (snyk.io)
CVSS 3.17.5HighCNA

Official description

Versions of the package jsrsasign before 11.1.1 are vulnerable to Infinite loop via the bnModInverse function in ext/jsbn2.js when the BigInteger.modInverse implementation receives zero or negative inputs, allowing an attacker to hang the process permanently by supplying such crafted values (e.g., modInverse(0, m) or modInverse(-1, m)).

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Loop with Unreachable Exit Condition

The product contains an iteration or loop with an exit condition that cannot be reached, i.e., an infinite loop.

More Loop with Unreachable Exit Condition vulnerabilities (CWE-835)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: poc, automatable: yes, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Other vulnerabilities in jsrsasign

All jsrsasign vulnerabilities

Recent Loop with Unreachable Exit Condition vulnerabilities

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