CVE-2026-5588 | Legion of the Bouncy Castle BC-JAVA up to 1.83 risky encryption

VDB-357693 · CVE-2026-5588 · GCVE-0-2026-5588 LEGION OF THE BOUNCY CASTLE BC-JAVA UP TO 1.83 RISKY ENCRYPTION HISTORYDIFFRELATEJSONXMLCTI CVSS Meta Temp Score Current Exploit Price (≈) CTI Interest Score 3.6 $0-$5k 3.65+ Summaryinfo 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. Performing a manipulation results in risky encryption. This vulnerability was named CVE-2026-5588. The attack may be initiated remotely. There is no available exploit. Upgrading the affected component is advised. Detailsinfo A vulnerability was found in Legion of the Bouncy Castle BC-JAVA up to 1.83. It has been classified as problematic. This affects an unknown function. The manipulation with an unknown input leads to a risky encryption vulnerability. CWE is classifying the issue as CWE-327. The product uses a broken or risky cryptographic algorithm or protocol. This is going to have an impact on confidentiality. The summary by CVE is: : Use of a Broken or Risky Cryptographic Algorithm vulnerability in Legion of the Bouncy Castle Inc. BC-JAVA bcpkix on all (pkix modules). PKIX draft CompositeVerifier accepts empty signature sequence as valid. This issue affects BC-JAVA: from 1.49 before 1.84. The advisory is shared at github.com. This vulnerability is uniquely identified as CVE-2026-5588 since 04/05/2026. The exploitability is told to be difficult. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 04/15/2026). MITRE ATT&CK project uses the attack technique T1600 for this issue. Upgrading to version 1.84 eliminates this vulnerability. Productinfo Type Programming Language Software Vendor Legion of the Bouncy Castle Name BC-JAVA Version 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 1.10 1.11 1.12 1.13 1.14 1.15 1.16 1.17 1.18 1.19 1.20 1.21 1.22 1.23 1.24 1.25 1.26 1.27 1.28 1.29 1.30 1.31 1.32 1.33 1.34 1.35 1.36 1.37 1.38 1.39 1.40 1.41 1.42 1.43 1.44 1.45 1.46 1.47 1.48 1.49 1.50 1.51 1.52 1.53 1.54 1.55 1.56 1.57 1.58 1.59 1.60 1.61 1.62 1.63 1.64 1.65 1.66 1.67 1.68 1.69 1.70 1.71 1.72 1.73 1.74 1.75 1.76 1.77 1.78 1.79 1.80 1.81 1.82 1.83 CPE 2.3info 🔒 🔒 🔒 CPE 2.2info 🔒 🔒 🔒 CVSSv4info VulDB Vector: 🔒 VulDB Reliability: 🔍 CNA CVSS-B Score: 🔒 CNA CVSS-BT Score: 🔒 CNA Vector: 🔒 CVSSv3info VulDB Meta Base Score: 3.7 VulDB Meta Temp Score: 3.6 VulDB Base Score: 3.7 VulDB Temp Score: 3.6 VulDB Vector: 🔒 VulDB Reliability: 🔍 CVSSv2info Vector Complexity Authentication Confidentiality Integrity Availability Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock VulDB Base Score: 🔒 VulDB Temp Score: 🔒 VulDB Reliability: 🔍 Exploitinginfo Class: Risky encryption CWE: CWE-327 / CWE-310 CAPEC: 🔒 ATT&CK: 🔒 Physical: No Local: No Remote: Yes Availability: 🔒 Status: Not defined Price Prediction: 🔍 Current Price Estimation: 🔒 0-Day Unlock Unlock Unlock Unlock Today Unlock Unlock Unlock Unlock Threat Intelligenceinfo Interest: 🔍 Active Actors: 🔍 Active APT Groups: 🔍 Countermeasuresinfo Recommended: Upgrade Status: 🔍 0-Day Time: 🔒 Upgrade: BC-JAVA 1.84 Timelineinfo 04/05/2026 CVE reserved 04/15/2026 +10 days Advisory disclosed 04/15/2026 +0 days VulDB entry created 04/15/2026 +0 days VulDB entry last update Sourcesinfo Advisory: github.com Status: Confirmed CVE: CVE-2026-5588 (🔒) GCVE (CVE): GCVE-0-2026-5588 GCVE (VulDB): GCVE-100-357693 Entryinfo Created: 04/15/2026 11:51 Changes: 04/15/2026 11:51 (68) Complete: 🔍 Cache ID: 99:0F5:101 Discussion No comments yet. Languages: en. Please log in to comment. ◂ PreviousOverviewNext ▸