# CVE-2026-87910: tarfile hardlink fallback ignores custom extraction filter rejection via None

CVE-2026-87910 is fixed in 34 products on 3 platforms, first by DEBIAN-CVE-2026-87910, released September 11, 2026. 10 other affected products have no fix yet. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2026-87910
- Priority: Routine
- CVSS: 5.7 (Moderate)
- EPSS: 0.0061
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Sep 11, 2026
- Weakness: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-87910

## Description

When tarfile extracts a link on a system that doesn't support links, it falls back to extracting a member from the archive. In this case, the filter function is run twice: once for the extracted member, and once with name set to the location of the link. For one of the calls, the return value was ignored. Instead, the member should be skipped if either call returns None.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Windows apps | Python 3.13 | 3.13.16 | [Python 3.13 3.13.16](https://patchblox.com/security/data/fix/windows-app/python.python.3.13-3.13.16.md) | Sep 30, 2026 |
| Windows apps | Python 3.14 | 3.14.9 | [Python 3.14 3.14.9](https://patchblox.com/security/data/fix/windows-app/python.python.3.14-3.14.9.md) | Oct 21, 2026 |
| Linux | pypy3 Debian 14 | 8.0.1+dfsg-1 | [DEBIAN-CVE-2026-87910](https://patchblox.com/security/data/fix/linux/debian-cve-2026-87910.md) | Sep 11, 2026 |
| Linux | python3.11 amzn 2023 | 3.11.17-1.amzn2023.0.1 | [ALAS2023-2026-3231](https://patchblox.com/security/data/fix/linux/alas2023-2026-3231.md) | Nov 7, 2026 |
| Linux | python3.11-debug amzn 2023 | 3.11.17-1.amzn2023.0.1 | [ALAS2023-2026-3231](https://patchblox.com/security/data/fix/linux/alas2023-2026-3231.md) | Nov 7, 2026 |
| Linux | python3.11-debuginfo amzn 2023 | 3.11.17-1.amzn2023.0.1 | [ALAS2023-2026-3231](https://patchblox.com/security/data/fix/linux/alas2023-2026-3231.md) | Nov 7, 2026 |
| Linux | python3.11-debugsource amzn 2023 | 3.11.17-1.amzn2023.0.1 | [ALAS2023-2026-3231](https://patchblox.com/security/data/fix/linux/alas2023-2026-3231.md) | Nov 7, 2026 |
| Linux | python3.11-devel amzn 2023 | 3.11.17-1.amzn2023.0.1 | [ALAS2023-2026-3231](https://patchblox.com/security/data/fix/linux/alas2023-2026-3231.md) | Nov 7, 2026 |
| Linux | python3.11-idle amzn 2023 | 3.11.17-1.amzn2023.0.1 | [ALAS2023-2026-3231](https://patchblox.com/security/data/fix/linux/alas2023-2026-3231.md) | Nov 7, 2026 |
| Linux | python3.11-libs amzn 2023 | 3.11.17-1.amzn2023.0.1 | [ALAS2023-2026-3231](https://patchblox.com/security/data/fix/linux/alas2023-2026-3231.md) | Nov 7, 2026 |
| Linux | python3.11-test amzn 2023 | 3.11.17-1.amzn2023.0.1 | [ALAS2023-2026-3231](https://patchblox.com/security/data/fix/linux/alas2023-2026-3231.md) | Nov 7, 2026 |
| Linux | python3.11-tkinter amzn 2023 | 3.11.17-1.amzn2023.0.1 | [ALAS2023-2026-3231](https://patchblox.com/security/data/fix/linux/alas2023-2026-3231.md) | Nov 7, 2026 |
| Linux | python3.12 amzn 2023 | 3.12.15-2.amzn2023.0.1 | [ALAS2023-2026-3230](https://patchblox.com/security/data/fix/linux/alas2023-2026-3230.md) | Nov 7, 2026 |
| Linux | python3.12-debug amzn 2023 | 3.12.15-2.amzn2023.0.1 | [ALAS2023-2026-3230](https://patchblox.com/security/data/fix/linux/alas2023-2026-3230.md) | Nov 7, 2026 |
| Linux | python3.12-debuginfo amzn 2023 | 3.12.15-2.amzn2023.0.1 | [ALAS2023-2026-3230](https://patchblox.com/security/data/fix/linux/alas2023-2026-3230.md) | Nov 7, 2026 |
| Linux | python3.12-debugsource amzn 2023 | 3.12.15-2.amzn2023.0.1 | [ALAS2023-2026-3230](https://patchblox.com/security/data/fix/linux/alas2023-2026-3230.md) | Nov 7, 2026 |
| Linux | python3.12-devel amzn 2023 | 3.12.15-2.amzn2023.0.1 | [ALAS2023-2026-3230](https://patchblox.com/security/data/fix/linux/alas2023-2026-3230.md) | Nov 7, 2026 |
| Linux | python3.12-idle amzn 2023 | 3.12.15-2.amzn2023.0.1 | [ALAS2023-2026-3230](https://patchblox.com/security/data/fix/linux/alas2023-2026-3230.md) | Nov 7, 2026 |
| Linux | python3.12-libs amzn 2023 | 3.12.15-2.amzn2023.0.1 | [ALAS2023-2026-3230](https://patchblox.com/security/data/fix/linux/alas2023-2026-3230.md) | Nov 7, 2026 |
| Linux | python3.12-test amzn 2023 | 3.12.15-2.amzn2023.0.1 | [ALAS2023-2026-3230](https://patchblox.com/security/data/fix/linux/alas2023-2026-3230.md) | Nov 7, 2026 |
| Linux | python3.12-tkinter amzn 2023 | 3.12.15-2.amzn2023.0.1 | [ALAS2023-2026-3230](https://patchblox.com/security/data/fix/linux/alas2023-2026-3230.md) | Nov 7, 2026 |
| Linux | python3.13 amzn 2023 | 3.13.16-1.amzn2023.0.1 | [ALAS2023-2026-3229](https://patchblox.com/security/data/fix/linux/alas2023-2026-3229.md) | Nov 7, 2026 |
| Linux | python3.13-debug amzn 2023 | 3.13.16-1.amzn2023.0.1 | [ALAS2023-2026-3229](https://patchblox.com/security/data/fix/linux/alas2023-2026-3229.md) | Nov 7, 2026 |
| Linux | python3.13-debuginfo amzn 2023 | 3.13.16-1.amzn2023.0.1 | [ALAS2023-2026-3229](https://patchblox.com/security/data/fix/linux/alas2023-2026-3229.md) | Nov 7, 2026 |
| Linux | python3.13-debugsource amzn 2023 | 3.13.16-1.amzn2023.0.1 | [ALAS2023-2026-3229](https://patchblox.com/security/data/fix/linux/alas2023-2026-3229.md) | Nov 7, 2026 |
| Linux | python3.13-devel amzn 2023 | 3.13.16-1.amzn2023.0.1 | [ALAS2023-2026-3229](https://patchblox.com/security/data/fix/linux/alas2023-2026-3229.md) | Nov 7, 2026 |
| Linux | python3.13-freethreading amzn 2023 | 3.13.16-1.amzn2023.0.1 | [ALAS2023-2026-3229](https://patchblox.com/security/data/fix/linux/alas2023-2026-3229.md) | Nov 7, 2026 |
| Linux | python3.13-freethreading-debug amzn 2023 | 3.13.16-1.amzn2023.0.1 | [ALAS2023-2026-3229](https://patchblox.com/security/data/fix/linux/alas2023-2026-3229.md) | Nov 7, 2026 |
| Linux | python3.13-idle amzn 2023 | 3.13.16-1.amzn2023.0.1 | [ALAS2023-2026-3229](https://patchblox.com/security/data/fix/linux/alas2023-2026-3229.md) | Nov 7, 2026 |
| Linux | python3.13-libs amzn 2023 | 3.13.16-1.amzn2023.0.1 | [ALAS2023-2026-3229](https://patchblox.com/security/data/fix/linux/alas2023-2026-3229.md) | Nov 7, 2026 |
| Linux | python3.13-test amzn 2023 | 3.13.16-1.amzn2023.0.1 | [ALAS2023-2026-3229](https://patchblox.com/security/data/fix/linux/alas2023-2026-3229.md) | Nov 7, 2026 |
| Linux | python3.13-tkinter amzn 2023 | 3.13.16-1.amzn2023.0.1 | [ALAS2023-2026-3229](https://patchblox.com/security/data/fix/linux/alas2023-2026-3229.md) | Nov 7, 2026 |
| Linux | python3.14 Debian 14 | 3.14.9-1 | [DEBIAN-CVE-2026-87910](https://patchblox.com/security/data/fix/linux/debian-cve-2026-87910.md) | Sep 11, 2026 |
| Linux | python3.15 Debian 14 | 3.15.0~rc3-1 | [DEBIAN-CVE-2026-87910](https://patchblox.com/security/data/fix/linux/debian-cve-2026-87910.md) | Sep 11, 2026 |

## No fix yet

| Platform | Product | Status |
|---|---|---|
| Windows apps | Python 2 | no-fix |
| Windows apps | Python 3.10 | no-fix |
| Windows apps | Python 3.11 | no-fix |
| Windows apps | Python 3.12 | no-fix |
| Windows apps | Python 3.5 | no-fix |
| Windows apps | Python 3.6 | no-fix |
| Windows apps | Python 3.7 | no-fix |
| Windows apps | Python 3.8 | no-fix |
| Windows apps | Python 3.9 | no-fix |
| macOS | Python3 | no-fix |

---

Data as of 2026-11-09T13:31:49Z 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

Free to use with attribution: show "Data: Patchblox Patch Radar" with a link to https://patchblox.com/security/patch-radar. Terms, including what needs a written agreement: https://patchblox.com/security/patch-radar/use-the-data

Product names, logos and trademarks shown on Patch Radar belong to their respective owners. They are used only to identify the software each security fix applies to and to help readers find their platform. Their use does not imply any affiliation with, or endorsement by, those owners, and Patchblox is not affiliated with any of them.