Password-based KDF cost parameters honoured unbounded from untrusted input across the remaining PBE entry points
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
CVE-2026-17508
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-17508
BC-JAVA
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
BC-JAVA
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
BC-LTS-JAVA
Source reference: /containers/cna/affected/2/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
BC-LTS-JAVA
Source reference: /containers/cna/affected/3/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
BC-FJA
Source reference: /containers/cna/affected/4/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://github.com/bcgit/bc-java",
"vendor": "Legion of the Bouncy Castle Inc.",
"modules": [
"pkix"
],
"product": "BC-JAVA",
"versions": [
{
"status": "affected",
"version": "0",
"lessThan": "1.86",
"versionType": "maven"
}
],
"platforms": [
"all"
],
"packageURL": "pkg:maven/org.bouncycastle/bcpkix-jdk18on",
"packageName": "bcpkix",
"programFiles": [
"JcePBMac1CalculatorBuilder",
"PKCS12PBEUtils",
"JcePKCSPBEInputDecryptorProviderBuilder",
"JceOpenSSLPKCS8DecryptorProviderBuilder"
],
"collectionURL": "https://www.bouncycastle.org/download/bouncy-castle-java/",
"defaultStatus": "unaffected"
},
{
"repo": "https://github.com/bcgit/bc-java",
"vendor": "Legion of the Bouncy Castle Inc.",
"modules": [
"core",
"prov"
],
"product": "BC-JAVA",
"versions": [
{
"status": "affected",
"version": "0",
"lessThan": "1.86",
"versionType": "maven"
}
],
"platforms": [
"all"
],
"packageURL": "pkg:maven/org.bouncycastle/bcprov-jdk18on",
"packageName": "bcprov",
"programFiles": [
"PBEPBKDF2",
"OpenSSHPrivateKeyUtil"
],
"collectionURL": "https://www.bouncycastle.org/download/bouncy-castle-java/",
"defaultStatus": "unaffected"
},
{
"repo": "https://github.com/bcgit/bc-lts-java",
"vendor": "Legion of the Bouncy Castle Inc.",
"modules": [
"pkix"
],
"product": "BC-LTS-JAVA",
"versions": [
{
"status": "affected",
"version": "2.73.0",
"lessThan": "2.73.13",
"versionType": "maven"
}
],
"platforms": [
"all"
],
"packageURL": "pkg:maven/org.bouncycastle/bcpkix-lts8on",
"packageName": "bcpkix-lts8on",
"programFiles": [
"JcePBMac1CalculatorBuilder",
"PKCS12PBEUtils",
"JcePKCSPBEInputDecryptorProviderBuilder",
"JceOpenSSLPKCS8DecryptorProviderBuilder"
],
"collectionURL": "https://www.bouncycastle.org/download/bouncy-castle-java-lts/",
"defaultStatus": "unaffected"
},
{
"repo": "https://github.com/bcgit/bc-lts-java",
"vendor": "Legion of the Bouncy Castle Inc.",
"modules": [
"core",
"prov"
],
"product": "BC-LTS-JAVA",
"versions": [
{
"status": "affected",
"version": "2.73.0",
"lessThan": "2.73.13",
"versionType": "maven"
}
],
"platforms": [
"all"
],
"packageURL": "pkg:maven/org.bouncycastle/bcprov-lts8on",
"packageName": "bcprov-lts8on",
"programFiles": [
"PBEPBKDF2",
"OpenSSHPrivateKeyUtil"
],
"collectionURL": "https://www.bouncycastle.org/download/bouncy-castle-java-lts/",
"defaultStatus": "unaffected"
},
{
"vendor": "Legion of the Bouncy Castle Inc.",
"product": "BC-FJA",
"versions": [
{
"status": "affected",
"version": "1.0.0",
"lessThan": "1.0.13",
"versionType": "maven"
},
{
"status": "affected",
"version": "2.0.0",
"lessThan": "2.0.13",
"versionType": "maven"
},
{
"status": "affected",
"version": "2.1.0",
"lessThan": "2.1.13",
"versionType": "maven"
}
],
"platforms": [
"all"
],
"packageURL": "pkg:maven/org.bouncycastle/bcpkix-fips",
"packageName": "bcpkix-fips",
"collectionURL": "https://www.bouncycastle.org/download/bouncy-castle-java-fips/",
"defaultStatus": "unaffected"
}
]- Related CVEs
- CVE-2026-17508
Source reference:
/cveMetadata/cveId
Publisher severity
medium
Source reference: /containers/cna/metrics
- Event
- #8080 · Revision 1
- Added to Heist Feed
- Publisher date