How severe is CVE-2026-13586?

CVE-2026-13586 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2026-13586 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (29th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-13586?

CVE-2026-13586 primarily affects Bouncycastle Bc-java. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-13586?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2026-13586 published?

CVE-2026-13586 was published on 2026-08-03 and last updated on 2026-08-28.

CVE-2026-13586

CVE-2026-13586 is a high-severity vulnerability in Bouncycastle Bc-java with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-770.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v4: 5.3
EPSS exploit prediction: 0% (29th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-770
Affected product: Bouncycastle Bc-java
Published: 2026-08-03
Last modified: 2026-08-28

Description

In Bouncy Castle for Java before 1.85, PKCS#12 MAC and bag-decryption KDF iteration-count bound (DoS). 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).

Frequently asked questions

What is CVE-2026-13586?: In Bouncy Castle for Java before 1.85, PKCS#12 MAC and bag-decryption KDF iteration-count bound (DoS). 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).
How severe is CVE-2026-13586?: CVE-2026-13586 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2026-13586 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (29th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-13586?: CVE-2026-13586 primarily affects Bouncycastle Bc-java. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-13586?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2026-13586 published?: CVE-2026-13586 was published on 2026-08-03 and last updated on 2026-08-28.

References

Affected products (3)

cpe:2.3:a:bouncycastle:bc-java:*:*:*:*:*:*:*:*
cpe:2.3:a:bouncycastle:bouncy_castle_for_java_lts:*:*:*:*:*:*:*:*
cpe:2.3:a:bouncycastle:fips_java_api:*:*:*:*:*:*:*:*

More vulnerabilities in Bouncycastle Bc-java

CVE-2007-6721 — Critical (CVSS 10.0): The Legion of the Bouncy Castle Java Cryptography API before release 1.38, as used in Crypto Provider Package before…
CVE-2018-1000613 — Critical (CVSS 9.8): Legion of the Bouncy Castle Legion of the Bouncy Castle Java Cryptography APIs 1.58 up to but not including 1.60…
CVE-2026-58062 — Critical (CVSS 9.1): In Bouncy Castle for Java before 1.85, Stapled OCSP response accepted without binding to the checked certificate. This…
CVE-2026-8763 — Critical (CVSS 9.1): In Bouncy Castle for Java before 1.85, Name Constraints bypass via trailing dot in rfc822Name and URI. This issue also…
CVE-2026-59650 — Critical (CVSS 9.1): In Bouncy Castle for Java before 1.85, MTI/A0 DH agreement exponentiates unvalidated peer value. This issue also…
CVE-2026-12817 — High (CVSS 8.6): In Bouncy Castle for Java before 1.85, OpenPGP AEAD decryption skips final tag on chunk-aligned data. This issue also…

All CVEs affecting Bouncycastle Bc-java →

Other CWE-770 (Allocation of Resources Without Limits or Throttling) vulnerabilities

CVE-2026-63299 — Critical (CVSS 9.9): An authorization bypass vulnerability in LXD allows an authenticated user to bypass project-level disk and volume…
CVE-2026-82439 — Critical (CVSS 9.8): Description The DRPC server kept a map from function name to request queue and created an entry the first time…
CVE-2026-47891 — Critical (CVSS 9.8): A Spring WebFlux application that relies on the Aalto XML processor to parse XML input does not correctly enforce the…
CVE-2026-74878 — Critical (CVSS 9.8): openssl_encrypt versions before 1.4.0 use an in-memory rate limiter for TOTP brute-force protection that is not shared…
CVE-2026-31283 — Critical (CVSS 9.8): In Totara LMS v19.1.5 and before, the forgot password API does not implement rate limiting for the target email…
CVE-2020-37067 — Critical (CVSS 9.8): Filetto 1.0 FTP server contains a denial of service vulnerability in the FEAT command processing that allows attackers…

Browse all CWE-770 (Allocation of Resources Without Limits or Throttling) vulnerabilities →