CVE-2026-63575 (GCVE-0-2026-63575)

Vulnerability from cvelistv5 – Published: 2026-10-02 07:06 – Updated: 2026-10-02 07:06
VLAI
Title
PKCS#12 key derivation loops about 2^32 times on a zero or negative iteration count
Summary
Loop with unreachable exit condition in the PKCS#12 key derivation (Pkcs12ParametersGenerator) in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows an attacker who can supply a PKCS#12 (PFX) file, or a PKCS#8 encrypted private key that uses a PKCS#12 password-based encryption algorithm, to cause a denial of service through CPU exhaustion via an iteration count of zero or below, because the derivation loop ran until its counter equalled the count, so for such a count it wrapped through about 2^32 iterations before the MAC or the password could be checked. A 75-byte PFX file with a negative MacData iteration count kept Pkcs12Store.Load busy for many minutes.
Severity
7.1 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
CWE
  • CWE-835 - Loop with Unreachable Exit Condition ('Infinite Loop')
Assigner
References
Impacted products
Vendor Product Version CPE status
Legion of the Bouncy Castle Inc. bc-csharp Affected: 0 , < 2.7.0 (semver)
guessed Create a notification for this product.
Credits
Paweł Łukasik (https://github.com/pawlos)
Show details on NVD website
To clipboard 

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          "packageName": "BouncyCastle.Cryptography",
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            "crypto/src/security/PbeUtilities.cs",
            "crypto/src/pkcs/Pkcs12Store.cs"
          ],
          "repo": "https://github.com/bcgit/bc-csharp",
          "vendor": "Legion of the Bouncy Castle Inc.",
          "versions": [
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              "status": "affected",
              "version": "0",
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          "type": "finder",
          "value": "Pawe\u0142 \u0141ukasik (https://github.com/pawlos)"
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          "url": "https://github.com/bcgit/bc-csharp/commit/0c7a6dfd64c4a479577e35a728a766721b79aba7"
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    "dateReserved": "2026-07-16T23:50:45.118Z",
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}



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