Medium severity · published Aug 3, 2026
CVE-2026-58063
BCFKS keystore load honours unbounded KDF cost from untrusted file
5.3
CVSS
0.4%
EPSS
No
On KEV
Description
In Bouncy Castle for Java before 1.85, BCFKS keystore load honours unbounded KDF cost from untrusted file. This issue also affects Bouncy Castle for Java LTS before 2.73.12, and Bouncy Castle for Java FIPS (BC-FJA) before bc-fips 1.0.2.7 (1.0.X series), 2.0.2 (2.0.X series) and 2.1.3 (2.1.X series).
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 36% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
BC
BC-FJA · Legion of the Bouncy Castle Inc.
1.0.0 before 1.0.2.7; 2.0.0 before 2.0.2; 2.1.0 before 2.1.3 · source: vendor
BC
BC-JAVA · Legion of the Bouncy Castle Inc.
before 1.85 · source: vendor, NVD
BC
BC-LTS-JAVA · Legion of the Bouncy Castle Inc.
2.73.0 before 2.73.12 · source: vendor
BC
Bouncy Castle For Java Lts · Bouncycastle
through 2.73.11 · source: NVD
FJ
Fips Java Api · Bouncycastle
1.0.0 before 1.0.2.7; 2.0.0 before 2.0.2; 2.1.0 before 2.1.3 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-58063
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-58063
Patch
https://github.com/bcgit/bc-java/commit/81737a56ef4489da1f849cf549df95e338ea6b06
Third Party Advisory
https://github.com/bcgit/bc-java/wiki/CVE%E2%80%902026%E2%80%9058063
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8.7
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8.7
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8.7
CVE-2026-13505
Zeroisation of sensitive key material on garbage collection relies on finalization
