CVE-2026-63578CWE-770denial-of-service

CVE-2026-63578

published October 2, 2026

CVSS
7.1
EPSS
0%
Percentile
24.9
In the wild
Unconfirmed
What it is

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 unauthenticated algorithm parameters without an upper bound and the key derivation runs before the password or the data can be checked. PKCS#5 PBES1 and PBES2 (PBKDF2), the PKCS#12 PBE algorithms and CMS password recipients (CmsPbeKey) are affected. Loading PKCS#12 files with Pkcs12Store is covered by CVE-2026-63572, and a zero or negative count with the PKCS#12 algorithms by CVE-2026-63575.

The record
Technical detail
CVSS
7.1 · NONE
CVSS v4.0
7.1 · 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
EPSS
0.00330 · 24.9th percentile
Weakness
CWE-770 · Allocation of Resources Without Limits or Throttling
Published
2026-10-02T12:17Z
References (6)
EPSS history
Timeline
  • 03 OCT 03:45Z
    EPSS moved — → 0%
    epss
  • 02 OCT 07:08Z
    Unbounded PBE iteration count when decrypting PKCS#8 private keys
    cvelistv5