Upstream information
Description
libass is a portable subtitle renderer for the ASS/SSA (Advanced Substation Alpha/Substation Alpha) subtitle format. From 0.17.4 until 0.17.5, libass event pruning does not guard negative Matroska `ReadOrder` values, allowing an attacker to clear arbitrarily many bits to zero at attacker-controlled positions near the NULL pointer. Exploitation requires a malicious Matroska stream loaded through `ass_process_chunk`, enabled read-order checking, and later pruning of the malicious events. Read-order checking is enabled by default unless `ass_set_check_readorder` is called with zero; pruning must occur explicitly through `ass_prune_events` or through automatic pruning previously enabled with `ass_configure_prune`. On common systems with arithmetic right shift, 32-bit int values, the upper address region reserved to the kernel, and matching binary/kernel architecture, the expected consequence is denial of service. More extensive exploitation on uncommon systems is theoretical and strongly constrained by the target addresses, bit-clearing-only mutation, and ASLR. This issue is fixed in version 0.17.5.SUSE information
Overall state of this security issue: Resolved
This issue is currently rated as having important severity.
| CVSS detail | SUSE |
|---|---|
| Base Score | 7.8 |
| Vector | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H |
| Attack Vector | Local |
| Attack Complexity | Low |
| Privileges Required | None |
| User Interaction | Required |
| Scope | Unchanged |
| Confidentiality Impact | High |
| Integrity Impact | High |
| Availability Impact | High |
| CVSSv3 Version | 3.1 |
| CVSS detail | CNA (GitHub) | SUSE |
|---|---|---|
| Base Score | 7.3 | 7.3 |
| Vector | CVSS:4.0/AV:L/AC:H/AT:N/PR:N/UI:P/VC:H/VI:H/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:X | CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N |
| Attack Vector | Local | Local |
| Attack Complexity | High | Low |
| Attack Requirements | None | Present |
| Privileges Required | None | None |
| User Interaction | Passive | Passive |
| Vulnerable System Confidentiality Impact | High | High |
| Vulnerable System Integrity Impact | High | High |
| 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 | libass | Not affected |
| SUSE Linux Enterprise High Performance Computing 12 | libass | Not affected |
| SUSE Linux Enterprise Module for Desktop Applications 15 SP7 | libass | Not affected |
| SUSE Linux Enterprise Server 15 SP7 | libass | Not affected |
| SUSE Linux Enterprise Server 16.0 | libass | Not affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP7 | libass | Not affected |
| SUSE Linux Enterprise Server for SAP applications 16.0 | libass | Not affected |
| openSUSE Leap 16.0 | libass | Not affected |
| Products under Long Term Service Pack support and receiving important and critical security fixes. | ||
| SUSE Linux Enterprise High Performance Computing 12 SP5 | libass | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS | libass | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS | libass | Not affected |
| SUSE Linux Enterprise Server 12 SP5 | libass | Not affected |
| SUSE Linux Enterprise Server 12 SP5-LTSS | libass | Not affected |
| SUSE Linux Enterprise Server 15 SP4-LTSS | libass | Not affected |
| SUSE Linux Enterprise Server 15 SP5-LTSS | libass | Not affected |
| SUSE Linux Enterprise Server 15 SP6-LTSS | libass | Not affected |
| SUSE Linux Enterprise Server LTSS Extended Security 12 SP5 | libass | Not affected |
| SUSE Linux Enterprise Server for SAP Applications 12 SP5 | libass | Not affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | libass | Not affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | libass | Not affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | libass | Not affected |
| Products past their end of life and not receiving proactive updates anymore. | ||
| HPE Helion OpenStack 8 | libass | Not affected |
| SUSE CaaS Platform 4.0 | libass | Not affected |
| SUSE Enterprise Storage 6 | libass | Not affected |
| SUSE Enterprise Storage 7 | libass | Not affected |
| SUSE Enterprise Storage 7.1 | libass | Not affected |
| SUSE Linux Enterprise Desktop 12 | libass | Not affected |
| SUSE Linux Enterprise Desktop 12 SP1 | libass | Not affected |
| SUSE Linux Enterprise Desktop 12 SP2 | libass | Not affected |
| SUSE Linux Enterprise Desktop 12 SP3 | libass | Not affected |
| SUSE Linux Enterprise Desktop 12 SP4 | libass | Not affected |
| SUSE Linux Enterprise Desktop 15 | libass | Not affected |
| SUSE Linux Enterprise Desktop 15 SP1 | libass | Not affected |
| SUSE Linux Enterprise Desktop 15 SP2 | libass | Not affected |
| SUSE Linux Enterprise Desktop 15 SP3 | libass | Not affected |
| SUSE Linux Enterprise Desktop 15 SP4 | libass | Not affected |
| SUSE Linux Enterprise Desktop 15 SP5 | libass | Not affected |
| SUSE Linux Enterprise Desktop 15 SP6 | libass | Not affected |
| SUSE Linux Enterprise High Performance Computing 12 SP1 | libass | Not affected |
| SUSE Linux Enterprise High Performance Computing 12 SP2 | libass | Not affected |
| SUSE Linux Enterprise High Performance Computing 12 SP3 | libass | Not affected |
| SUSE Linux Enterprise High Performance Computing 12 SP4 | libass | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 | libass | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 SP1 | libass | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 SP1-ESPOS | libass | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 SP1-LTSS | libass | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 SP2 | libass | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 SP2-ESPOS | libass | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 SP2-LTSS | libass | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 SP3 | libass | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 SP3-ESPOS | libass | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 SP3-LTSS | libass | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4 | libass | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS | libass | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5 | libass | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS | libass | Not affected |
| SUSE Linux Enterprise High Performance Computing 15-ESPOS | libass | Not affected |
| SUSE Linux Enterprise High Performance Computing 15-LTSS | libass | Not affected |
| SUSE Linux Enterprise Module for Desktop Applications 15 | libass | Not affected |
| SUSE Linux Enterprise Module for Desktop Applications 15 SP1 | libass | Not affected |
| SUSE Linux Enterprise Module for Desktop Applications 15 SP2 | libass | Not affected |
| SUSE Linux Enterprise Module for Desktop Applications 15 SP3 | libass | Not affected |
| SUSE Linux Enterprise Module for Desktop Applications 15 SP4 | libass | Not affected |
| SUSE Linux Enterprise Module for Desktop Applications 15 SP5 | libass | Not affected |
| SUSE Linux Enterprise Module for Desktop Applications 15 SP6 | libass | Not affected |
| SUSE Linux Enterprise Module for Package Hub 15 SP4 | libass | Not affected |
| SUSE Linux Enterprise Module for Package Hub 15 SP5 | libass | Not affected |
| SUSE Linux Enterprise Point of Sale 12 SP2-CLIENT | libass | Not affected |
| SUSE Linux Enterprise Real Time 15 SP2 | libass | Not affected |
| SUSE Linux Enterprise Real Time 15 SP3 | libass | Not affected |
| SUSE Linux Enterprise Real Time 15 SP4 | libass | Not affected |
| SUSE Linux Enterprise Server 12 | libass | Not affected |
| SUSE Linux Enterprise Server 12 SP1 | libass | Not affected |
| SUSE Linux Enterprise Server 12 SP1-LTSS | libass | Not affected |
| SUSE Linux Enterprise Server 12 SP2 | libass | Not affected |
| SUSE Linux Enterprise Server 12 SP2-BCL | libass | Not affected |
| SUSE Linux Enterprise Server 12 SP2-ESPOS | libass | Not affected |
| SUSE Linux Enterprise Server 12 SP2-LTSS | libass | Not affected |
| SUSE Linux Enterprise Server 12 SP3 | libass | Not affected |
| SUSE Linux Enterprise Server 12 SP3-BCL | libass | Not affected |
| SUSE Linux Enterprise Server 12 SP3-ESPOS | libass | Not affected |
| SUSE Linux Enterprise Server 12 SP3-LTSS | libass | Not affected |
| SUSE Linux Enterprise Server 12 SP4 | libass | Not affected |
| SUSE Linux Enterprise Server 12 SP4-ESPOS | libass | Not affected |
| SUSE Linux Enterprise Server 12 SP4-LTSS | libass | Not affected |
| SUSE Linux Enterprise Server 12-LTSS | libass | Not affected |
| SUSE Linux Enterprise Server 15 | libass | Not affected |
| SUSE Linux Enterprise Server 15 SP1 | libass | Not affected |
| SUSE Linux Enterprise Server 15 SP1-BCL | libass | Not affected |
| SUSE Linux Enterprise Server 15 SP1-LTSS | libass | Not affected |
| SUSE Linux Enterprise Server 15 SP2 | libass | Not affected |
| SUSE Linux Enterprise Server 15 SP2-BCL | libass | Not affected |
| SUSE Linux Enterprise Server 15 SP2-LTSS | libass | Not affected |
| SUSE Linux Enterprise Server 15 SP3 | libass | Not affected |
| SUSE Linux Enterprise Server 15 SP3-BCL | libass | Not affected |
| SUSE Linux Enterprise Server 15 SP3-LTSS | libass | Not affected |
| SUSE Linux Enterprise Server 15 SP4 | libass | Not affected |
| SUSE Linux Enterprise Server 15 SP5 | libass | Not affected |
| SUSE Linux Enterprise Server 15 SP6 | libass | Not affected |
| SUSE Linux Enterprise Server 15-LTSS | libass | Not affected |
| SUSE Linux Enterprise Server for Raspberry Pi 12 SP2 | libass | Not affected |
| SUSE Linux Enterprise Server for SAP Applications 12 | libass | Not affected |
| SUSE Linux Enterprise Server for SAP Applications 12 SP1 | libass | Not affected |
| SUSE Linux Enterprise Server for SAP Applications 12 SP2 | libass | Not affected |
| SUSE Linux Enterprise Server for SAP Applications 12 SP3 | libass | Not affected |
| SUSE Linux Enterprise Server for SAP Applications 12 SP4 | libass | Not affected |
| SUSE Linux Enterprise Server for SAP Applications 15 | libass | Not affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP1 | libass | Not affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP2 | libass | Not affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP3 | libass | Not affected |
| SUSE Linux Enterprise Software Development Kit 12 | libass | Not affected |
| SUSE Linux Enterprise Software Development Kit 12 SP1 | libass | Not affected |
| SUSE Linux Enterprise Software Development Kit 12 SP2 | libass | Not affected |
| SUSE Linux Enterprise Software Development Kit 12 SP3 | libass | Not affected |
| SUSE Linux Enterprise Software Development Kit 12 SP4 | libass | Not affected |
| SUSE Linux Enterprise Software Development Kit 12 SP5 | libass | Not affected |
| SUSE Manager Proxy 4.0 | libass | Not affected |
| SUSE Manager Proxy 4.1 | libass | Not affected |
| SUSE Manager Proxy 4.2 | libass | Not affected |
| SUSE Manager Proxy 4.3 | libass | Not affected |
| SUSE Manager Retail Branch Server 4.0 | libass | Not affected |
| SUSE Manager Retail Branch Server 4.1 | libass | Not affected |
| SUSE Manager Retail Branch Server 4.2 | libass | Not affected |
| SUSE Manager Retail Branch Server 4.3 | libass | Not affected |
| SUSE Manager Server 4.0 | libass | Not affected |
| SUSE Manager Server 4.1 | libass | Not affected |
| SUSE Manager Server 4.2 | libass | Not affected |
| SUSE Manager Server 4.3 | libass | Not affected |
| SUSE OpenStack Cloud 7 | libass | Not affected |
| SUSE OpenStack Cloud 8 | libass | Not affected |
| SUSE OpenStack Cloud 9 | libass | Not affected |
| SUSE OpenStack Cloud Crowbar 8 | libass | Not affected |
| SUSE OpenStack Cloud Crowbar 9 | libass | Not affected |
| openSUSE Leap 15.3 | libass | Not affected |
| openSUSE Leap 15.4 | libass | Not affected |
| openSUSE Leap 15.5 | libass | Not affected |
| openSUSE Leap 15.6 | libass | Not affected |
SUSE Timeline for this CVE
CVE page created: Sat Oct 31 13:45:09 2026CVE page last modified: Sat Oct 31 13:45:09 2026