CVE-2026-63575: Loop with Unreachable Exit Condition
Source GCVE Database
Not known to be exploited · CVSS 7.1 High : upgrade to 2.7.0 soon.
Data as of 28 Oct 2026, 17:11 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 9% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 2.7.0
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 2 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade bc-csharp and BouncyCastle.Cryptography to 2.7.0.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Legion of the Bouncy Castle Inc.bc-csharp | Affected
| Fixed in
|
NuGetBouncyCastle.Cryptographypkg:nuget/BouncyCastle.CryptographyOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Users of Bouncy Castle bc-csharp should upgrade to version 2.7.0 or later once available, as the vulnerability affects versions before 2.7.0. If you cannot patch yet, avoid processing untrusted PKCS#12 or PKCS#8 files with potentially manipulated iteration counts.
Description
A vulnerability in the PKCS#12 key derivation implementation (Pkcs12ParametersGenerator) of Bouncy Castle Inc. bc-csharp before version 2.7.0 allows denial of service via CPU exhaustion. This occurs when an attacker supplies a PKCS#12 (PFX) file or PKCS#8 encrypted private key with a password-based encryption algorithm using an iteration count of zero or below. The derivation loop runs excessively due to an unreachable exit condition, causing the process to hang for extended periods.
References
- nvd.nist.gov/vuln/detail/CVE-2026-63575 (opens in a new tab)
- github.com/bcgit/bc-csharp/commit/0c7a6dfd64c4a479577e35a728a766721b79aba7 (opens in a new tab)
- github.com/bcgit/bc-csharp/commit/7c0ed15f9783c9595b1a53f3900136461fd944f4 (opens in a new tab)
- github.com/bcgit/bc-csharp/wiki/CVE-2026-63575 (opens in a new tab)