Upstream information
Description
In Bouncy Castle for Java before 1.86, the MLS implementation (org.bouncycastle.mls) holds RFC 9420's uint32 leaf_index in a signed int, so a wire value with the top bit set decodes to a negative number. That is a legitimate encoding rather than malformed input, and it must still decode, since the MLS interop test vectors round-trip the full range. GroupKeySet.SecretTree.hasLeaf and Group.validateRemove compared the decoded value directly against the tree's leaf count, and a signed comparison treats any negative int as less than a positive bound, so an out-of-range sender passed the membership check. In the hasLeaf case the SenderData of an unprotected PrivateMessage could then drive LeafIndex.directPath through NodeIndex.parent() arithmetic that never reaches the tree root, growing the resulting node list without bound until the JVM exhausted its heap. A single small message from any current group member could therefore deny service to every other member of the group. Both comparisons now interpret the value as unsigned via Integer.toUnsignedLong, rejecting an out-of-range sender however it was encoded; well-formed leaf indices are unaffected.SUSE information
Overall state of this security issue: Pending
This issue is currently rated as having moderate severity.
| CVSS detail | SUSE |
|---|---|
| Base Score | 6.5 |
| Vector | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
| Attack Vector | Network |
| Attack Complexity | Low |
| Privileges Required | Low |
| User Interaction | None |
| Scope | Unchanged |
| Confidentiality Impact | None |
| Integrity Impact | None |
| Availability Impact | High |
| CVSSv3 Version | 3.1 |
| CVSS detail | CNA (91579145-5d7b-4cc5-b925-a0262ff19630) | SUSE |
|---|---|---|
| Base Score | 8.7 | 7.1 |
| Vector | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/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:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N |
| Attack Vector | Network | Network |
| Attack Complexity | Low | Low |
| Attack Requirements | None | None |
| Privileges Required | None | Low |
| User Interaction | None | None |
| Vulnerable System Confidentiality Impact | None | None |
| Vulnerable System Integrity Impact | None | None |
| Vulnerable System Availability Impact | High | High |
| Subsequent System Confidentiality Impact | None | None |
| Subsequent System Integrity Impact | None | None |
| Subsequent System Availability Impact | None | None |
| CVSSv4 Version | 4.0 | 4.0 |
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 | Affected |
| SUSE Linux Enterprise Module for Development Tools 15 SP7 | bouncycastle | Affected |
| SUSE Linux Enterprise Server 15 SP7 | bouncycastle | Affected |
| 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 | Affected |
| 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 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5 | bouncycastle | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS | bouncycastle | Affected |
| 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 | Affected |
| SUSE Linux Enterprise Server 15 SP5 | bouncycastle | Affected |
| SUSE Linux Enterprise Server 15 SP5-LTSS | bouncycastle | Affected |
| SUSE Linux Enterprise Server 15 SP6 | bouncycastle | Affected |
| SUSE Linux Enterprise Server 15 SP6-LTSS | bouncycastle | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | bouncycastle | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | bouncycastle | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | bouncycastle | Affected |
| 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 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS | bouncycastle | Affected |
| 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 for NVIDIA 16.1 | bouncycastle | Affected |
| Container Status | ||
| containers/apache-pulsar:3.3 | bouncycastle | Affected |
SUSE Timeline for this CVE
CVE page created: Fri Oct 2 15:33:56 2026CVE page last modified: Fri Oct 2 17:35:24 2026