CVE-2026-5598
published 2026-04-15CVE-2026-5598: 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…
PriorityP347high7.5CVSS 3.1
AVNACLPRNUINSUCHINAN
EPSS
0.90%
56.6th percentile
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
3 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| legion_of_the_bouncy_castle_inc | bc-java | >= 1.71 < 1.80.2 | 1.80.2 |
| legion_of_the_bouncy_castle_inc | bc-java | >= 1.81 < 1.81.1 | 1.81.1 |
| legion_of_the_bouncy_castle_inc | bc-java | >= 1.82 < 1.84 | 1.84 |
CVSS provenance
nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
nvdv4.08.9HIGHCVSS:4.0/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
vendor_redhat10.0CRITICAL
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GHSA
Bouncy Castle Has Covert Timing Channel Vulnerability
ghsa·2026-04-17
CVE-2026-5598 [HIGH] CWE-385 Bouncy Castle Has Covert Timing Channel Vulnerability
Bouncy Castle Has Covert Timing Channel Vulnerability
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.
GHSA
GHSA-p93r-85wp-75v3: Covert timing channel vulnerability in Legion of the Bouncy Castle Inc
ghsa_unreviewed·2026-04-17
CVE-2026-5598 [CRITICAL] CWE-385 GHSA-p93r-85wp-75v3: Covert timing channel vulnerability in Legion of the Bouncy Castle Inc
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.
VulDB
Legion of the Bouncy Castle BC-JAVA up to 1.83 Private Key covert timing channel
vuldb·2026-04-15·CVSS 10.0
CVE-2026-5598 [CRITICAL] Legion of the Bouncy Castle BC-JAVA up to 1.83 Private Key covert timing channel
A vulnerability was found in Legion of the Bouncy Castle BC-JAVA up to 1.83. It has been rated as problematic. The affected element is an unknown function of the component Private Key Handler. Performing a manipulation results in covert timing channel.
This vulnerability was named CVE-2026-5598. The attack may be initiated remotely. There is no available exploit.
Upgrading the affected component is advised.
Red Hat
bouncycastle: BC-JAVA: private key leakage via non-constant time comparisons
vendor_redhat·2026-04-15·CVSS 10.0
CVE-2026-5598 [CRITICAL] CWE-385 bouncycastle: BC-JAVA: private key leakage via non-constant time comparisons
bouncycastle: BC-JAVA: private key leakage via non-constant time comparisons
A flaw was found in Legion of the Bouncy Castle Inc. BC-JAVA core. A covert timing channel vulnerability, caused by non-constant time comparisons, risks the leakage of private keys in the FrodoKEM implementation. An unauthenticated, remote attacker can potentially exploit this timing discrepancy to gain unauthorized access to sensitive cryptographic information.
Statement: To exploit this issue, an unauthenticated attacker needs to send highly specific, malformed ciphertexts to the target server. These payloads are used to interact with the private key of the server in a way that the vulnerable, non-constant time code paths are triggered during the verification step. An attack typically requires sending a large
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2026-5598 pdfbox: private key leakage via non-constant time comparisons [fedora-all]
bugzilla·2026-04-17·CVSS 10.0
CVE-2026-5598 [CRITICAL] CVE-2026-5598 pdfbox: private key leakage via non-constant time comparisons [fedora-all]
CVE-2026-5598 pdfbox: private key leakage via non-constant time comparisons [fedora-all]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
Bugzilla
CVE-2026-5598 bouncycastle: BC-JAVA: private key leakage via non-constant time comparisons
bugzilla·2026-04-15·CVSS 10.0
CVE-2026-5598 [CRITICAL] CVE-2026-5598 bouncycastle: BC-JAVA: private key leakage via non-constant time comparisons
CVE-2026-5598 bouncycastle: BC-JAVA: private key leakage via non-constant time comparisons
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.
https://github.com/bcgit/bc-java/commit/8692e6b2b191fc4aafa32545c7a78bdb9bf110c5https://github.com/bcgit/bc-java/commit/94abbd56413dfdac651fd878bc60253871ef5e87https://github.com/bcgit/bc-java/wiki/CVE%E2%80%902026%E2%80%905598https://access.redhat.com/errata/RHSA-2026:12267https://access.redhat.com/errata/RHSA-2026:12269https://access.redhat.com/errata/RHSA-2026:18054https://access.redhat.com/errata/RHSA-2026:18055https://access.redhat.com/errata/RHSA-2026:18059https://access.redhat.com/errata/RHSA-2026:53644https://access.redhat.com/errata/RHSA-2026:53806https://access.redhat.com/security/cve/CVE-2026-5598https://bugzilla.redhat.com/show_bug.cgi?id=2458635https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-5598.json
2026-04-15
Published