Legion of the Bouncy Castle bc-csharp up to 2.6.x Pkcs12 Keystore Loading Pkcs12Store.Load allocation of resources

Summaryinfo

A vulnerability has been found in Legion of the Bouncy Castle bc-csharp up to 2.6.x and classified as problematic. This affects the function Pkcs12Store.Load of the component Pkcs12 Keystore Loading. The manipulation leads to allocation of resources. This vulnerability is listed as CVE-2026-63572. The attack may be initiated remotely. There is no available exploit. The affected component should be upgraded.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in Legion of the Bouncy Castle bc-csharp up to 2.6.x. This issue affects the function Pkcs12Store.Load of the component Pkcs12 Keystore Loading. The manipulation with an unknown input leads to a allocation of resources vulnerability. Using CWE to declare the problem leads to CWE-770. The product allocates a reusable resource or group of resources on behalf of an actor without imposing any restrictions on the size or number of resources that can be allocated, in violation of the intended security policy for that actor. Impacted is availability. The summary by CVE is:

Allocation of resources without limits in PKCS#12 keystore loading (Pkcs12Store.Load) in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows an attacker who can supply a PKCS#12 (PFX) file to cause a denial of service through CPU exhaustion via an iteration count close to 2^31 in the file's MacData or in the PBE parameters of an encrypted SafeContents or shrouded key bag, because the counts are taken from the file without an upper bound and the key derivation runs before the MAC or the password can be checked. A zero or negative count is covered by CVE-2026-63575. Pkcs12Utilities.ConvertToDefiniteLength is also affected.

It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2026-63572 since 07/17/2026. The exploitation is known to be easy. The attack may be initiated remotely. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1499 according to MITRE ATT&CK.

Upgrading to version 2.7.0 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2026-3713). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

• Open Source Bouncy Castle

Productinfo

Vendor

• Legion of the Bouncy Castle

Name

• bc-csharp

Version

• 2.0
• 2.1
• 2.2
• 2.3
• 2.4
• 2.5
• 2.6

CPE 2.3info

• 🔒
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CPE 2.2info

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Entryinfo

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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