Is CVE-2026-63578 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-63578 being exploited in the wild.

How severe is CVE-2026-63578?

Informational severity, published 2 October 2026.

Which products and versions are affected?

Legion of the Bouncy Castle BouncyCastle.Cryptography before 2.7.0.

Is there a fix for CVE-2026-63578?

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

How is CVE-2026-63578 attacked?

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

Am I affected by CVE-2026-63578?

Check whether you run Legion of the Bouncy Castle BouncyCastle.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-2026-63578: Bouncy Castle Cryptography unbounded resource allocation in password-based key decryption

CVE-2026-63578 · Severity: info · Published 2026-10-02

The Bouncy Castle Cryptography Library is a .NET cryptographic library used to encrypt private keys and handle secure communications. An attacker who can provide a specially crafted encrypted private key file can cause a denial of service by forcing the library to consume excessive CPU resources during key decryption, impacting any application using this library to load encrypted keys.

Technologies: Legion of the Bouncy Castle BouncyCastle.Cryptography. Vendors: Legion of the Bouncy Castle.

Quick answers

Is CVE-2026-63578 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-63578 being exploited in the wild.
How severe is CVE-2026-63578?: Informational severity, published 2 October 2026.
Which products and versions are affected?: Legion of the Bouncy Castle BouncyCastle.Cryptography before 2.7.0.
Is there a fix for CVE-2026-63578?: Yes: fixed in BouncyCastle.Cryptography 2.7.0. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-63578 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-63578?: Check whether you run Legion of the Bouncy Castle BouncyCastle.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: BouncyCastle.Cryptography 2.7.0

Technical details

The vulnerability exists in PbeUtilities.GenerateCipherParameters and related password-based encryption (PBES1, PBES2/PBKDF2, PKCS#12 PBE, and CMS password recipients) functions, which fail to validate the iteration count parameter before performing key derivation. An attacker supplying an encrypted private key with an iteration count close to 2^31 can trigger CPU exhaustion. The key derivation computation occurs before any password or data validation, making the attack trivial to execute.

Affected products

Legion of the Bouncy Castle BouncyCastle.Cryptography before 2.7.0

Timeline

2026-10-02: disclosed

References

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