PatchTheCVECVE-2026-63578: Allocation of resources without limits in password-based private-key decryption (PbeUtilities.GenerateCipherPa
CVE-2026-63578 is a high-severity flaw (CVSS 7.5) affecting bc-csharp. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
Allocation of resources without limits in password-based private-key decryption (PbeUtilities.GenerateCipherParameters) in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows an attacker who can supply an encrypted private key, such as a PKCS#8 EncryptedPrivateKeyInfo or "ENCRYPTED PRIVATE KEY" PEM file, to cause a denial of service through CPU exhaustion via an iteration count close to 2^31, because the count is taken from the unauthe
Why this priority
- High severity
- Remotely exploitable, no login, no user action
A fixed release or distro patch exists.
Risk facts
| CVSS score | 7.5 (High) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 0.3% (top 74%) |
| CISA exploited list | No |
| Weakness | CWE-770 |
| Published | 2026-10-02 |
| Last modified | 2026-10-28 |
Last updated 2026-10-28 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2026-63578?
bc-csharp: upgrade to 2.7.0. Exact commands for each OS are on this page.
Is CVE-2026-63578 being exploited?
CVE-2026-63578 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2026-63578 affect?
CVE-2026-63578 affects bc-csharp. Severity is high (CVSS 7.5). Allocation of resources without limits in password-based private-key decryption (PbeUtilities.GenerateCipherParameters) in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows an attacker who can supply an encrypted private key, s
How urgent is CVE-2026-63578?
Priority 38/100. High severity; Remotely exploitable, no login, no user action
Related CVEs
- CVE-2026-63569 MEDIUM 6.5 UPGRADE Improper input validation in DHAgreement.CalculateAgreement (MTI/A0 two-pass Diffie-Hellman) in Legion of the
- CVE-2026-103600 HIGH 7.5 UPGRADE Uncontrolled recursion in the ASN.1 parser (Asn1InputStream, Asn1StreamParser) in Legion of the Bouncy Castle
- CVE-2026-103601 HIGH 7.5 UPGRADE Release of unverified plaintext in the CCM (CcmBlockCipher) and DSTU 7624 CCM (KCcmBlockCipher) AEAD modes in
- CVE-2026-63575 HIGH 7.5 UPGRADE Loop with unreachable exit condition in the PKCS#12 key derivation (Pkcs12ParametersGenerator) in Legion of th
- CVE-2026-63576 HIGH 7.5 UPGRADE Improper certificate validation in PkixNameConstraintValidator (ExtractHostFromURL) in Legion of the Bouncy Ca