CVE-2026-5598
Non-constant time comparisons risk private key leakage in FrodoKEM.
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 1.84.
INFO
Published Date :
April 15, 2026, 10:16 a.m.
Last Modified :
April 21, 2026, 4:16 p.m.
Remotely Exploit :
Yes !
Source :
91579145-5d7b-4cc5-b925-a0262ff19630
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 4.0 | CRITICAL | 91579145-5d7b-4cc5-b925-a0262ff19630 | ||||
| CVSS 4.0 | CRITICAL | 91579145-5d7b-4cc5-b925-a0262ff19630 | ||||
| CVSS 4.0 | HIGH | 91579145-5d7b-4cc5-b925-a0262ff19630 |
Solution
- Update BC-JAVA core to version 1.84 or later.
- Ensure FrodoKEM implementations use constant-time comparisons.
- Consult vendor advisories for specific patches and guidance.
Public PoC/Exploit Available at Github
CVE-2026-5598 has a 1 public
PoC/Exploit available at Github.
Go to the Public Exploits tab to see the list.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-5598.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-5598 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-5598
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
None
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-5598 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-5598 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by 91579145-5d7b-4cc5-b925-a0262ff19630
Apr. 21, 2026
Action Type Old Value New Value Added Reference https://github.com/bcgit/bc-java/wiki/CVE%E2%80%902026%E2%80%905598 Removed Reference https://github.com/bcgit/bc-java/wiki/CVE%E2%80%902026%E2%80%905998 -
CVE Modified by 91579145-5d7b-4cc5-b925-a0262ff19630
Apr. 21, 2026
Action Type Old Value New Value Changed Description Covert timing channel vulnerability in Legion of the Bouncy Castle Inc. BC-JAVA core on all (core modules). Non-constant time comparisons risk private key leakage in FrodoKEM. This issue affects BC-JAVA: from 2.17.3 before 1.84. 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 1.84. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:H/SI:H/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:P/AU:Y/R:X/V:X/RE:X/U:Red Removed CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added Reference https://github.com/bcgit/bc-java/commit/8692e6b2b191fc4aafa32545c7a78bdb9bf110c5 Added Reference https://github.com/bcgit/bc-java/commit/94abbd56413dfdac651fd878bc60253871ef5e87 -
New CVE Received by 91579145-5d7b-4cc5-b925-a0262ff19630
Apr. 15, 2026
Action Type Old Value New Value Added Description Covert timing channel vulnerability in Legion of the Bouncy Castle Inc. BC-JAVA core on all (core modules). Non-constant time comparisons risk private key leakage in FrodoKEM. This issue affects BC-JAVA: from 2.17.3 before 1.84. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CWE CWE-385 Added Reference https://github.com/bcgit/bc-java/wiki/CVE%E2%80%902026%E2%80%905998