Quick answer
Direct answer
Risk scores
| CVSS metric | What it means |
|---|---|
| Attack vector (AV:N) | Network: reachable remotely |
| Attack complexity (AC:H) | High complexity |
| Attack requirements (AT:N) | No attack requirements |
| Privileges required (PR:N) | No privileges required |
| User interaction (UI:N) | No user interaction |
| Confidentiality (VC:H) | High confidentiality impact |
| Integrity (VI:H) | High integrity impact |
| Availability (VA:N) | No availability impact |
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/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
About Kjur Jsrsasign
CVE-2026-4600 affects Kjur Jsrsasign, a product from Kjur. Before acting, confirm where Kjur Jsrsasign runs in your estate, who owns it and whether it is reachable from the internet, because exposure decides real risk more than the score alone.
What the flaw is
In plain terms: Versions of the package jsrsasign before 11.1.1 are vulnerable to Improper Verification of Cryptographic Signature via the DSA domain-parameter validation in KJUR.crypto.DSA.setPublic (and the related DSA/X509 verification flow in src/dsa-2.0.js). An attacker can forge DSA signatures or X.509 certificates that X509.verifySignature() accepts by supplying malicious domain parameters such as g=1, y=1, and a fixed r=1, which make the verification equation true for any hash.
Based on its CVSS vector, the flaw can be reached over the network, needs no login, and needs no user interaction. Apply the vendor fix and confirm exposure on internet facing and business critical assets first.
Affected versions and timeline
| Field | Detail |
|---|---|
| Product | Kjur Jsrsasign |
| Affected versions | Jsrsasign before 11.1.1 |
| Published | Mar 23, 2026 |
| Last modified | Sep 10, 2026 |
| Added to CISA KEV | Not listed |
| Assigning CNA | report@snyk.io |
How to detect it
- Inventory every instance of Kjur Jsrsasign and record the running version against the affected range above.
- Check external attack surface scans for internet facing instances of the component.
- Review logs on affected systems for unusual requests, errors or new processes around the vulnerable function.
- Confirm with an authenticated vulnerability scan once your scanner has a check for this CVE.
How to fix it
- Apply the fixed version of Kjur Jsrsasign named in the vendor advisory.
- If patching must wait, restrict network access to the affected service and put it behind authentication or a web application firewall rule.
- Rescan after the change to prove the exposure is gone, then close the ticket.
CTEM action plan
| CTEM stage | What to do for this CVE |
|---|---|
| Scope | Add every business service that depends on Kjur Jsrsasign to the current CTEM cycle. |
| Discover | Find all instances, including shadow and cloud deployments, and record versions and exposure. |
| Prioritize | Rank using EPSS and CVSS together with asset exposure and business impact. |
| Validate | Confirm the flaw is reachable and exploitable in your environment and that compensating controls work. |
| Mobilize | Assign the fix to the asset owner with a due date matched to the priority, then verify closure. |
CWE References
Technical References
- ▸NVD entry
- ▸CVE.org record
- ▸GitHub repository reference
- ▸Fix commit on GitHub
- ▸GitHub issue or pull request
- ▸Snyk vulnerability report
- ▸Snyk vulnerability report
- ▸Red Hat security advisory
- ▸Red Hat security advisory
- ▸Red Hat security advisory
- ▸Red Hat security advisory
- ▸Red Hat security advisory
- ▸Red Hat security advisory
- ▸Red Hat security advisory
- ▸Red Hat security advisory
- ▸Red Hat security advisory
- ▸Red Hat security advisory
Frequently asked questions
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