How severe is CVE-2026-5598?

No CVSS score has been assigned to CVE-2026-5598 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2026-5598?

CVE-2026-5598 affects the following packages: org.bouncycastle:bcprov-jdk15to18 (Maven), org.bouncycastle:bcprov-jdk14 (Maven), org.bouncycastle:bcprov-jdk18on (Maven). Ecosystems affected: Maven.

How do I fix CVE-2026-5598?

Update org.bouncycastle:bcprov-jdk15to18 to 1.80.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-5598 is resolved across your whole dependency graph.

How do I detect CVE-2026-5598 in my Maven dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.bouncycastle:bcprov-jdk15to18. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

How do I mitigate CVE-2026-5598 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

How does O3 Security protect against CVE-2026-5598?

O3 pinpoints whether CVE-2026-5598 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is CVE-2026-5598 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-5598 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2026-5598?

CVE-2026-5598 has an EPSS (Exploit Prediction Scoring System) score of 0.7%, placing it in the 49th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

When was CVE-2026-5598 published, and has it been updated?

CVE-2026-5598 was published on April 15, 2026 and was last updated on July 31, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

☕ Maven

CVE-2026-5598

CVE-2026-5598 is a security vulnerability in org.bouncycastle:bcprov-jdk15to18. O3 Security confirms whether CVE-2026-5598 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.

Non-constant time comparisons risk private key leakage in FrodoKEM.

Also known asGHSA-p93r-85wp-75v3

Published

Apr 15, 2026

Updated

Jul 31, 2026

Affected

3 pkgs

Patched

3 / 3

Exploits

None indexed

EPSS Exploitation Probability

via FIRST.org ↗

0.7%probability of exploitation in next 30 days

Lower Risk49th percentile0.00%

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Blast Radius

3 pkgs affected

☕org.bouncycastle:bcprov-jdk15to18☕org.bouncycastle:bcprov-jdk14☕org.bouncycastle:bcprov-jdk18on

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.

Description

Covert timing channel vulnerability in Legion of the Bouncy Castle Inc. BC-JAVA core on all (core modules).

This vulnerability is associated with program files FrodoEngine.Java.

This issue affects BC-JAVA: from 1.71 before 1.80.2, from 1.81 before 1.81.1, from 1.82 before 1.84.

Affected Packages

3 total 3 fixed

Ecosystem	Package	Vulnerable range	Fix
☕Maven	`org.bouncycastle:bcprov-jdk15to18`	≥ 1.71&&< 1.80.2	1.80.2
☕Maven	`org.bouncycastle:bcprov-jdk14`	≥ 1.81&&< 1.81.1	1.81.1
☕Maven	`org.bouncycastle:bcprov-jdk18on`	≥ 1.82&&< 1.84	1.84

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.bouncycastle:bcprov-jdk15to18. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update org.bouncycastle:bcprov-jdk15to18 to 1.80.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-5598 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-5598 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to CVE-2026-5598. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

Covert timing channel vulnerability in Legion of the Bouncy Castle Inc. BC-JAVA core on all (core modules). This vulnerability is associated with program files FrodoEngine.Java. This issue affects BC-JAVA: from 1.71 before 1.80.2, from 1.81 before 1.81.1, from 1.82 before 1.84.

O3 Security · Impact-Aware SCA

Is CVE-2026-5598 in your dependencies?

O3 detects CVE-2026-5598 across Maven dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

Scan my dependencies How O3 SCA works