Upstream information

CVE-2026-71891 at MITRE

Description

In Bouncy Castle for Java before 1.86, BLS12_381BasicScheme.keyValidate, and so BLSPublicKeyParameters and every BasicScheme, MessageAugmentation and ProofOfPossession verify and aggregateVerify that gate on it, accepted a public key built on a foreign ECCurve that merely shares BLS12-381's field characteristic. The prime-order subgroup check trusts a point's own curve to name its cofactor, since ECPoint.satisfiesOrder returns true outright when the curve's cofactor is one, so a point on a curve with a different equation and a cofactor forged to one passed keyValidate despite not being a G1 point at all. In BC's pairing implementation such a point contributes the identity in the target group, so an aggregate signature verified against a set of public keys including it is accepted even though it contains no signature for that key and message pair, admitting a phantom signer. keyValidate now first confirms that the point's curve carries exactly the canonical G1 field, equation, order and cofactor before any subgroup check. The issue is reachable only where an application constructs an ECPoint on an explicit, non-canonical curve and accepts it as an authority-bearing key; the standard 48-byte compressed-point decoder always supplies the canonical curve and was never affected.

SUSE information

Overall state of this security issue: Pending

This issue is currently rated as having moderate severity.

CVSS v3 Scores
CVSS detail SUSE
Base Score 5.9
Vector CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
Attack Vector Network
Attack Complexity High
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality Impact None
Integrity Impact High
Availability Impact None
CVSSv3 Version 3.1
CVSS v4 Scores
CVSS detail CNA (91579145-5d7b-4cc5-b925-a0262ff19630) SUSE
Base Score 7.1 8.2
Vector CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/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:Amber CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
Attack Vector Network Network
Attack Complexity Low Low
Attack Requirements None Present
Privileges Required None None
User Interaction Passive None
Vulnerable System Confidentiality Impact None None
Vulnerable System Integrity Impact High High
Vulnerable System Availability Impact None None
Subsequent System Confidentiality Impact None None
Subsequent System Integrity Impact None None
Subsequent System Availability Impact None None
CVSSv4 Version 4.0 4.0
SUSE Bugzilla entry: 1284220 [IN_PROGRESS]

No SUSE Security Announcements cross referenced.

List of packages in QA

Product(s) Package(s)
SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS
  • bouncycastle >= 1.86-150200.3.41.1
  • bouncycastle-pg >= 1.86-150200.3.41.1
  • bouncycastle-pkix >= 1.86-150200.3.41.1
  • bouncycastle-util >= 1.86-150200.3.41.1
SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS
  • bouncycastle >= 1.86-150200.3.41.1
  • bouncycastle-pg >= 1.86-150200.3.41.1
  • bouncycastle-pkix >= 1.86-150200.3.41.1
  • bouncycastle-util >= 1.86-150200.3.41.1
SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS
  • bouncycastle >= 1.86-150200.3.41.1
  • bouncycastle-pg >= 1.86-150200.3.41.1
  • bouncycastle-pkix >= 1.86-150200.3.41.1
  • bouncycastle-util >= 1.86-150200.3.41.1
SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS
  • bouncycastle >= 1.86-150200.3.41.1
  • bouncycastle-pg >= 1.86-150200.3.41.1
  • bouncycastle-pkix >= 1.86-150200.3.41.1
  • bouncycastle-util >= 1.86-150200.3.41.1
SUSE Linux Enterprise Module for Development Tools 15 SP7
  • bouncycastle >= 1.86-150200.3.41.1
  • bouncycastle-pg >= 1.86-150200.3.41.1
  • bouncycastle-pkix >= 1.86-150200.3.41.1
  • bouncycastle-util >= 1.86-150200.3.41.1
SUSE Linux Enterprise Server 15 SP7
  • bouncycastle >= 1.86-150200.3.41.1
  • bouncycastle-pg >= 1.86-150200.3.41.1
  • bouncycastle-pkix >= 1.86-150200.3.41.1
  • bouncycastle-util >= 1.86-150200.3.41.1
SUSE Linux Enterprise Desktop 15 SP7
  • bouncycastle >= 1.86-150200.3.41.1
  • bouncycastle-pg >= 1.86-150200.3.41.1
  • bouncycastle-pkix >= 1.86-150200.3.41.1
  • bouncycastle-util >= 1.86-150200.3.41.1
SUSE Linux Enterprise Server for SAP Applications 15 SP7
  • bouncycastle >= 1.86-150200.3.41.1
  • bouncycastle-pg >= 1.86-150200.3.41.1
  • bouncycastle-pkix >= 1.86-150200.3.41.1
  • bouncycastle-util >= 1.86-150200.3.41.1
SUSE Linux Enterprise Server 15 SP4-LTSS
  • bouncycastle >= 1.86-150200.3.41.1
  • bouncycastle-pg >= 1.86-150200.3.41.1
  • bouncycastle-pkix >= 1.86-150200.3.41.1
  • bouncycastle-util >= 1.86-150200.3.41.1
SUSE Linux Enterprise Server 15 SP4-LTSS
  • bouncycastle >= 1.86-150200.3.41.1
  • bouncycastle-pg >= 1.86-150200.3.41.1
  • bouncycastle-pkix >= 1.86-150200.3.41.1
  • bouncycastle-util >= 1.86-150200.3.41.1
SUSE Linux Enterprise Server 15 SP5-LTSS
  • bouncycastle >= 1.86-150200.3.41.1
  • bouncycastle-pg >= 1.86-150200.3.41.1
  • bouncycastle-pkix >= 1.86-150200.3.41.1
  • bouncycastle-util >= 1.86-150200.3.41.1
SUSE Linux Enterprise Server 15 SP5-LTSS
  • bouncycastle >= 1.86-150200.3.41.1
  • bouncycastle-pg >= 1.86-150200.3.41.1
  • bouncycastle-pkix >= 1.86-150200.3.41.1
  • bouncycastle-util >= 1.86-150200.3.41.1
SUSE Linux Enterprise Server 15 SP6-LTSS
  • bouncycastle >= 1.86-150200.3.41.1
  • bouncycastle-pg >= 1.86-150200.3.41.1
  • bouncycastle-pkix >= 1.86-150200.3.41.1
  • bouncycastle-util >= 1.86-150200.3.41.1
SUSE Linux Enterprise Server 15 SP6-LTSS
  • bouncycastle >= 1.86-150200.3.41.1
  • bouncycastle-pg >= 1.86-150200.3.41.1
  • bouncycastle-pkix >= 1.86-150200.3.41.1
  • bouncycastle-util >= 1.86-150200.3.41.1
SUSE Linux Enterprise Server for SAP Applications 15 SP4
  • bouncycastle >= 1.86-150200.3.41.1
  • bouncycastle-pg >= 1.86-150200.3.41.1
  • bouncycastle-pkix >= 1.86-150200.3.41.1
  • bouncycastle-util >= 1.86-150200.3.41.1
SUSE Linux Enterprise Server for SAP Applications 15 SP5
  • bouncycastle >= 1.86-150200.3.41.1
  • bouncycastle-pg >= 1.86-150200.3.41.1
  • bouncycastle-pkix >= 1.86-150200.3.41.1
  • bouncycastle-util >= 1.86-150200.3.41.1
SUSE Linux Enterprise Server for SAP Applications 15 SP6
  • bouncycastle >= 1.86-150200.3.41.1
  • bouncycastle-pg >= 1.86-150200.3.41.1
  • bouncycastle-pkix >= 1.86-150200.3.41.1
  • bouncycastle-util >= 1.86-150200.3.41.1

Status of this issue by product and package

Please note that this evaluation state might be work in progress, incomplete or outdated. Also information for service packs in the LTSS phase is only included for issues meeting the LTSS criteria. If in doubt, feel free to contact us for clarification. The updates are grouped by state of their lifecycle. SUSE product lifecycles are documented on the lifecycle page.

Product(s) Source package State
Products under general support and receiving all security fixes.
SUSE Linux Enterprise Desktop 15 SP7 bouncycastle In progress
SUSE Linux Enterprise Module for Development Tools 15 SP7 bouncycastle In progress
SUSE Linux Enterprise Server 15 SP7 bouncycastle In progress
SUSE Linux Enterprise Server 16.0 bouncycastle Affected
SUSE Linux Enterprise Server 16.1 bouncycastle Affected
SUSE Linux Enterprise Server for SAP Applications 15 SP7 bouncycastle In progress
SUSE Linux Enterprise Server for SAP applications 16.0 bouncycastle Affected
SUSE Linux Enterprise Server for SAP applications 16.1 bouncycastle Affected
openSUSE Leap 16.0 bouncycastle Affected
Products under Long Term Service Pack support and receiving important and critical security fixes.
SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS bouncycastle In progress
SUSE Linux Enterprise High Performance Computing 15 SP5 bouncycastle Affected
SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS bouncycastle In progress
SUSE Linux Enterprise Module for Development Tools 15 SP4 bouncycastle Affected
SUSE Linux Enterprise Module for Development Tools 15 SP5 bouncycastle Affected
SUSE Linux Enterprise Module for Development Tools 15 SP6 bouncycastle Affected
SUSE Linux Enterprise Server 15 SP4 bouncycastle Affected
SUSE Linux Enterprise Server 15 SP4-LTSS bouncycastle In progress
SUSE Linux Enterprise Server 15 SP5 bouncycastle Affected
SUSE Linux Enterprise Server 15 SP5-LTSS bouncycastle In progress
SUSE Linux Enterprise Server 15 SP6 bouncycastle Affected
SUSE Linux Enterprise Server 15 SP6-LTSS bouncycastle In progress
SUSE Linux Enterprise Server for SAP Applications 15 SP4 bouncycastle In progress
SUSE Linux Enterprise Server for SAP Applications 15 SP5 bouncycastle In progress
SUSE Linux Enterprise Server for SAP Applications 15 SP6 bouncycastle In progress
Products past their end of life and not receiving proactive updates anymore.
SUSE Enterprise Storage 7 bouncycastle Affected
SUSE Enterprise Storage 7.1 bouncycastle Affected
SUSE Linux Enterprise Desktop 15 SP2 bouncycastle Affected
SUSE Linux Enterprise Desktop 15 SP3 bouncycastle Affected
SUSE Linux Enterprise Desktop 15 SP4 bouncycastle Affected
SUSE Linux Enterprise Desktop 15 SP5 bouncycastle Affected
SUSE Linux Enterprise Desktop 15 SP6 bouncycastle Affected
SUSE Linux Enterprise High Performance Computing 15 SP2 bouncycastle Affected
SUSE Linux Enterprise High Performance Computing 15 SP2-ESPOS bouncycastle Affected
SUSE Linux Enterprise High Performance Computing 15 SP2-LTSS bouncycastle Affected
SUSE Linux Enterprise High Performance Computing 15 SP3 bouncycastle Affected
SUSE Linux Enterprise High Performance Computing 15 SP3-ESPOS bouncycastle Affected
SUSE Linux Enterprise High Performance Computing 15 SP3-LTSS bouncycastle Affected
SUSE Linux Enterprise High Performance Computing 15 SP4 bouncycastle Affected
SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS bouncycastle In progress
SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS bouncycastle In progress
SUSE Linux Enterprise Module for Development Tools 15 SP2 bouncycastle Affected
SUSE Linux Enterprise Module for Development Tools 15 SP3 bouncycastle Affected
SUSE Linux Enterprise Real Time 15 SP2 bouncycastle Affected
SUSE Linux Enterprise Real Time 15 SP3 bouncycastle Affected
SUSE Linux Enterprise Real Time 15 SP4 bouncycastle Affected
SUSE Linux Enterprise Server 15 SP2 bouncycastle Affected
SUSE Linux Enterprise Server 15 SP2-BCL bouncycastle Affected
SUSE Linux Enterprise Server 15 SP2-LTSS bouncycastle Affected
SUSE Linux Enterprise Server 15 SP3 bouncycastle Affected
SUSE Linux Enterprise Server 15 SP3-BCL bouncycastle Affected
SUSE Linux Enterprise Server 15 SP3-LTSS bouncycastle Affected
SUSE Linux Enterprise Server for SAP Applications 15 SP2 bouncycastle Affected
SUSE Linux Enterprise Server for SAP Applications 15 SP3 bouncycastle Affected
SUSE Manager Proxy 4.1 bouncycastle Affected
SUSE Manager Proxy 4.2 bouncycastle Affected
SUSE Manager Proxy 4.3 bouncycastle Affected
SUSE Manager Retail Branch Server 4.1 bouncycastle Affected
SUSE Manager Retail Branch Server 4.2 bouncycastle Affected
SUSE Manager Retail Branch Server 4.3 bouncycastle Affected
SUSE Manager Server 4.1 bouncycastle Affected
SUSE Manager Server 4.2 bouncycastle Affected
SUSE Manager Server 4.3 bouncycastle Affected
openSUSE Leap 15.3 bouncycastle Affected
openSUSE Leap 15.4 bouncycastle Affected
openSUSE Leap 15.5 bouncycastle Affected
openSUSE Leap 15.6 bouncycastle Affected
Products at an unknown state of their lifecycle.
SUSE Linux Enterprise Server 16.2 bouncycastle Analysis
SUSE Linux Enterprise Server for NVIDIA 16.1 bouncycastle Affected
Container Status
containers/apache-pulsar:3.3 bouncycastleAffected

SUSE Timeline for this CVE

CVE page created: Mon Oct 5 16:44:23 2026
CVE page last modified: Fri Oct 9 15:50:10 2026