# CVE-2026-107886: OpenPrinting CUPS before 2.4.20 contains a double-free in printer-class management. When CUPS-Add-Modify-Class replaces an existing class member list, add_class() frees pclass->printers without clearing the pointer. If subsequent validation fails, the class retains the dangling pointer; CUPS-Delete-Class subsequently frees the same allocation in cupsdDeletePrinter(). A client authorized to modify and delete classes can cause scheduler-wide denial of service. The default policy requires @SYSTEM privileges.

CVE-2026-107886 is fixed in 15 products on 1 platform, first by ALAS2023-2026-3415, released November 10, 2026. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2026-107886
- Priority: Routine
- CVSS: 2.3 (Low)
- EPSS: 0.0024
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Oct 10, 2026
- Weakness: Double Free
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-107886

## Description

OpenPrinting CUPS before 2.4.20 contains a double-free in printer-class management. When CUPS-Add-Modify-Class replaces an existing class member list, add_class() frees pclass->printers without clearing the pointer. If subsequent validation fails, the class retains the dangling pointer; CUPS-Delete-Class subsequently frees the same allocation in cupsdDeletePrinter(). A client authorized to modify and delete classes can cause scheduler-wide denial of service. The default policy requires @SYSTEM privileges.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | cups amzn 2023 | 1:2.4.20-1.amzn2023.0.1 | [ALAS2023-2026-3415](https://patchblox.com/security/data/fix/linux/alas2023-2026-3415.md) | Nov 10, 2026 |
| Linux | cups-client amzn 2023 | 1:2.4.20-1.amzn2023.0.1 | [ALAS2023-2026-3415](https://patchblox.com/security/data/fix/linux/alas2023-2026-3415.md) | Nov 10, 2026 |
| Linux | cups-client-debuginfo amzn 2023 | 1:2.4.20-1.amzn2023.0.1 | [ALAS2023-2026-3415](https://patchblox.com/security/data/fix/linux/alas2023-2026-3415.md) | Nov 10, 2026 |
| Linux | cups-debuginfo amzn 2023 | 1:2.4.20-1.amzn2023.0.1 | [ALAS2023-2026-3415](https://patchblox.com/security/data/fix/linux/alas2023-2026-3415.md) | Nov 10, 2026 |
| Linux | cups-debugsource amzn 2023 | 1:2.4.20-1.amzn2023.0.1 | [ALAS2023-2026-3415](https://patchblox.com/security/data/fix/linux/alas2023-2026-3415.md) | Nov 10, 2026 |
| Linux | cups-devel amzn 2023 | 1:2.4.20-1.amzn2023.0.1 | [ALAS2023-2026-3415](https://patchblox.com/security/data/fix/linux/alas2023-2026-3415.md) | Nov 10, 2026 |
| Linux | cups-filesystem amzn 2023 | 1:2.4.20-1.amzn2023.0.1 | [ALAS2023-2026-3415](https://patchblox.com/security/data/fix/linux/alas2023-2026-3415.md) | Nov 10, 2026 |
| Linux | cups-ipptool amzn 2023 | 1:2.4.20-1.amzn2023.0.1 | [ALAS2023-2026-3415](https://patchblox.com/security/data/fix/linux/alas2023-2026-3415.md) | Nov 10, 2026 |
| Linux | cups-ipptool-debuginfo amzn 2023 | 1:2.4.20-1.amzn2023.0.1 | [ALAS2023-2026-3415](https://patchblox.com/security/data/fix/linux/alas2023-2026-3415.md) | Nov 10, 2026 |
| Linux | cups-libs amzn 2023 | 1:2.4.20-1.amzn2023.0.1 | [ALAS2023-2026-3415](https://patchblox.com/security/data/fix/linux/alas2023-2026-3415.md) | Nov 10, 2026 |
| Linux | cups-libs-debuginfo amzn 2023 | 1:2.4.20-1.amzn2023.0.1 | [ALAS2023-2026-3415](https://patchblox.com/security/data/fix/linux/alas2023-2026-3415.md) | Nov 10, 2026 |
| Linux | cups-lpd amzn 2023 | 1:2.4.20-1.amzn2023.0.1 | [ALAS2023-2026-3415](https://patchblox.com/security/data/fix/linux/alas2023-2026-3415.md) | Nov 10, 2026 |
| Linux | cups-lpd-debuginfo amzn 2023 | 1:2.4.20-1.amzn2023.0.1 | [ALAS2023-2026-3415](https://patchblox.com/security/data/fix/linux/alas2023-2026-3415.md) | Nov 10, 2026 |
| Linux | cups-printerapp amzn 2023 | 1:2.4.20-1.amzn2023.0.1 | [ALAS2023-2026-3415](https://patchblox.com/security/data/fix/linux/alas2023-2026-3415.md) | Nov 10, 2026 |
| Linux | cups-printerapp-debuginfo amzn 2023 | 1:2.4.20-1.amzn2023.0.1 | [ALAS2023-2026-3415](https://patchblox.com/security/data/fix/linux/alas2023-2026-3415.md) | Nov 10, 2026 |

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Data as of 2026-11-11T13:47:35Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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