Vulnerabilities

Vulnerability · CVE-2026-103604

Inefficient algorithmic complexity in X.509 distinguished name string conversion (X509Name.ToString and IetfUtilities.ValueToString) in Legion of the Bouncy Castle Inc.

Published Oct 2, 2026 · catalog updated Oct 28, 2026 · Inefficient algorithmic complexity in

Last checked Oct 28, 2026. A connected source was read within the last 7 days.

Check if you run it

No confirmed exploitation is on record for CVE-2026-103604. EPSS is 0.31%. Act only if a listed version of Inefficient algorithmic complexity in is installed.

Gaps on this record

  • The stored product name is a package slug. The name on this page is taken from the title (Inefficient algorithmic complexity in).
  • No vendor fix or required action is stored. Compare the linked advisory before you change production.

Same product and reporting

Severity
High8.7
Known exploitation
Not in CISA/VulnCheck KEV
EPSS
0.31%
Remediation
Version ranges on file
Affected products
cpe bouncycastle/bc-csharp

Inefficient algorithmic complexity in X.509 distinguished name string conversion (X509Name.ToString and IetfUtilities.ValueToString) in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows a remote unauthenticated attacker to cause a denial of service through CPU exhaustion via a certificate, CRL, certification request or other structure whose name contains a long attribute value made up of characters that must be escaped, such as commas, or of leading or trailing spaces, because each escaping backslash was inserted into the buffer being scanned, so the work grew quadratically with the length of the value. Applications are exposed when they convert such a name to a string, for example to log or display it, or compare it with IetfUtilities.RdnAreEqual, as PKIX path validation does for directoryName name constraints.

Are you affected?

Enter the version you run. The result uses only the ranges stored on this record.

The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.

  • cpe bouncycastle/bc-csharp< 2.7.0

How to fix CVE-2026-103604

  • Upgrade

    CVE-2026-103604 lists a fix boundary at 2.7.0. Compare the installed build with that boundary before you change production.

  • Version check

    Affected < 2.7.0

  • Advisory

    Open the cve_org record and follow its fix.

  • Official advisories

What to do

Three questions, each answered from this record only. Confirm the vendor advisory before you patch.

Should you patch?

No confirmed exploitation is on record for CVE-2026-103604. EPSS is 0.31%. Act only if a listed version of Inefficient algorithmic complexity in is installed.

Which versions are affected?

Compare what you have installed with < 2.7.0. Compare the installed version with the linked vendor advisory before you change production.

What should an analyst verify?

CWE-407. EPSS 0.31%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.

Code

The project this record applies to. Exploit listings stay in References.

Timeline

Detection, updates, and resolution for this record.

  1. Oct 2, 2026 · NIST NVD

    Detected

    Inefficient algorithmic complexity in X.509 distinguished name string conversion (X509Name.ToString and IetfUtilities.ValueToString) in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows a remote unauthenticated attacker to cause a denial of service through CPU exhaustion via a certificate, CRL, certification request or other structure whose name contains a long attribute value made up

  2. Oct 28, 2026 · NIST NVD

    Updated

    Inefficient algorithmic complexity in X.509 distinguished name string conversion (X509Name.ToString and IetfUtilities.ValueToString) in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows a remote unauthenticated attacker to cause a denial of service through CPU exhaustion via a certificate, CRL, certification request or other structure whose name contains a long attribute value made up

Sources

  • CVE.orgVulnerability recordCVE-2026-103604

    Official CVE identifier

    cve.org
  • NIST NVDVulnerability recordCVE-2026-103604

    Inefficient algorithmic complexity in X.509 distinguished name string conversion (X509Name.ToString and IetfUtilities.ValueToString) in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows a remote unauthenticated attacker to cause a denial of service through CPU exhaus

    nvd.nist.gov

References

Freshness

Last verified in this catalog Oct 28, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.

  • CVE.orgOct 28, 2026
  • NIST NVDOct 28, 2026