Answer in brief
CVE-2026-17508 records a Medium severity (CVSS 5.3) vulnerability in Password-based KDF cost parameters honoured unbounded from untrusted input across the remaining PBE entry points. The current sources do not mark it as known exploited. The current feed maps Legion of the Bouncy Castle Inc./bcpkix (generic), Legion of the Bouncy Castle Inc./bcpkix-fips (generic), Legion of the Bouncy Castle Inc./bcpkix-lts8on (generic), Legion of the Bouncy Castle Inc./bcprov (generic) and additional mapped packages. Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 5.3. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Legion of the Bouncy Castle Inc./bcpkix (generic), Legion of the Bouncy Castle Inc./bcpkix-fips (generic), Legion of the Bouncy Castle Inc./bcpkix-lts8on (generic), Legion of the Bouncy Castle Inc./bcprov (generic) and additional mapped packages. Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Legion of the Bouncy Castle Inc./bcpkixgeneric | >=0 <1.86 | 1.86 |
| Legion of the Bouncy Castle Inc./bcpkix-fipsgeneric | >=1.0.0 <1.0.13 || >=2.0.0 <2.0.13 || >=2.1.0 <2.1.13 | 1.0.13, 2.0.13, 2.1.13 |
| Legion of the Bouncy Castle Inc./bcpkix-lts8ongeneric | >=2.73.0 <2.73.13 | 2.73.13 |
| Legion of the Bouncy Castle Inc./bcprovgeneric | >=0 <1.86 | 1.86 |
| Legion of the Bouncy Castle Inc./bcprov-lts8ongeneric | >=2.73.0 <2.73.13 | 2.73.13 |
Published upstream
Oct 2, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 2, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Oct 2, 2026
In Bouncy Castle for Java before 1.86, several password-based key derivation entry points ran the KDF with cost parameters taken from the untrusted input being processed, without bounding them, so a small input could dictate an arbitrary amount of work before any password or integrity check could reject it. The affected paths are the RFC 9579 PBMAC1 MAC calculator builders, which took the PBKDF2 iteration count and derived-key length straight out of PBMAC1Params (JcePBMac1CalculatorBuilder, and PKCS12PBEUtils.createPBMac1Calculator reached from PKCS12PfxPdu.isMacValid); the scrypt parallelization parameter p in the PKCS#8 and PKCS#12 cost guards, which bounded only the cost parameter N and the block size r even though the scratch buffer scales with r times p, so the configured memory ceiling could be evaded entirely; the raw JCA PBKDF2 provider (org.bouncycastle.jcajce.provider.symmetric.PBEPBKDF2); and the bcrypt round count read from an encrypted OpenSSH v1 private key's own kdfoptions. Each now bounds the parameter before deriving, in line with the caps already applied elsewhere in the tree, with the OpenSSH round count configurable through the new org.bouncycastle.openssh.max_rounds property. This completes the bounding begun in 1.85 for the PKCS#8 / PBES2 decryptors (CVE-2026-15055). This issue also affects Bouncy Castle for Java LTS before 2.73.13, and Bouncy Castle for Java FIPS (BC-FJA) before bcpkix-fips 1.0.13 (1.0.X series), 2.0.13 (2.0.X series) and 2.1.13 (2.1.X series).
Quoted source text, attributed separately from HOL analysis.