Is CVE-2026-63572 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-63572 being exploited in the wild.

How severe is CVE-2026-63572?

Informational severity, published 2 October 2026.

Which products and versions are affected?

Legion of the Bouncy Castle Bouncy Castle Cryptography before 2.7.0.

Is there a fix for CVE-2026-63572?

Yes: fixed in 2.7.0. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-63572 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-63572?

Check whether you run Legion of the Bouncy Castle Bouncy Castle Cryptography at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-63572: Bouncy Castle Cryptography DoS via unbounded iteration count in PKCS#12

CVE-2026-63572 · Severity: info · Published 2026-10-02

Bouncy Castle Cryptography is a widely-used cryptography library for .NET that processes digital certificates and encrypted keystores. An attacker who provides a specially crafted PKCS#12 keystore file can cause the application to freeze or become unresponsive by setting extremely large iteration counts in password-based encryption parameters, forcing the library to waste CPU resources on unnecessary cryptographic operations before validating the file's integrity.

Vendors: Legion of the Bouncy Castle.

Quick answers

Is CVE-2026-63572 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-63572 being exploited in the wild.
How severe is CVE-2026-63572?: Informational severity, published 2 October 2026.
Which products and versions are affected?: Legion of the Bouncy Castle Bouncy Castle Cryptography before 2.7.0.
Is there a fix for CVE-2026-63572?: Yes: fixed in 2.7.0. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-63572 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-63572?: Check whether you run Legion of the Bouncy Castle Bouncy Castle Cryptography at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

Fixed in: 2.7.0

Technical details

A resource exhaustion vulnerability exists in Pkcs12Store.Load and Pkcs12Utilities.ConvertToDefiniteLength where iteration counts from the PKCS#12 file's MacData or PBE parameters are used without an upper bound check. An attacker can set counts near 2^31, causing the key derivation function to execute excessively before the file's MAC or password can be validated, leading to denial of service through CPU exhaustion. The library requires the supplied PKCS#12 file as input, making this a reachable attack vector for applications that load user-supplied keystores.

Affected products

Legion of the Bouncy Castle Bouncy Castle Cryptography before 2.7.0

Timeline

2026-10-02: disclosed

References

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