# CVE-2026-15806: `HTTPPasswordMgr` can send saved HTTPS credentials via HTTP because of incorrect scheme matching

CVE-2026-15806 is fixed in 59 products on 3 platforms, first by DEBIAN-CVE-2026-15806, released September 12, 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-2026-15806
- Priority: Routine
- CVSS: 6.0 (Moderate)
- EPSS: 0.0053
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Aug 18, 2026
- Weakness: Cleartext Transmission of Sensitive Information
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-15806

## Description

The HTTPPasswordMgr class in the urllib.request module, along with its subclasses HTTPPasswordMgrWithDefaultRealm and HTTPPasswordMgrWithPriorAuth, did not take the URL scheme into account when matching stored credentials against a requested URL. Credentials added for an https:// URL were also used for requests to the same host over http://, so an attacker able to redirect or downgrade a client to plain HTTP (for example, via an HTTPS-to-HTTP redirect or an on-path position) could capture credentials in cleartext. Credentials added for http:// URLs could likewise be sent over https://.  Credential matching is now scoped by URL scheme. Credentials registered with a URL that includes a scheme are only used for requests with the same scheme. Credentials registered with a bare authority (such as example.com or example.com:8080) continue to match any scheme, preserving compatibility with existing code, including proxy authentication.  Users who cannot upgrade immediately can mitigate by ensuring that applications never make plain http:// requests to hosts for which credentials are registered, for example by not following redirects to http:// URLs.

## 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 | 3.14.8 | [Python 3.14 3.14.8](https://patchblox.com/security/data/fix/windows-app/python.python.3.14-3.14.8.md) | Sep 30, 2026 |
| Linux | pypy3 Debian 14 | 8.0.1+dfsg-1 | [DEBIAN-CVE-2026-15806](https://patchblox.com/security/data/fix/linux/debian-cve-2026-15806.md) | Sep 12, 2026 |
| Linux | python sles 15.7 | 2.7.18-150000.133.1 | [SUSE-SU-2026:4411-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-4411-1.md) | Oct 1, 2026 |
| Linux | python-base sles 15.7 | 2.7.18-150000.133.1 | [SUSE-SU-2026:4411-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-4411-1.md) | Oct 1, 2026 |
| Linux | python3 sles 15.6 | 3.6.15-150300.10.129.1 | [SUSE-SU-2026:4754-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-4754-1.md) | Nov 7, 2026 |
| Linux | python3 sles 15.7 | 3.6.15-150300.10.129.1 | [SUSE-SU-2026:4754-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-4754-1.md) | Nov 7, 2026 |
| Linux | python3-core sles 15.6 | 3.6.15-150300.10.129.1 | [SUSE-SU-2026:4754-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-4754-1.md) | Nov 7, 2026 |
| Linux | python3-core sles 15.7 | 3.6.15-150300.10.129.1 | [SUSE-SU-2026:4754-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-4754-1.md) | Nov 7, 2026 |
| Linux | python3.11 Debian 12.15 (bookworm) | 3.11.2-6+deb12u9 | [DEBIAN-CVE-2026-15806](https://patchblox.com/security/data/fix/linux/debian-cve-2026-15806.md) | Sep 12, 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 | 3.14.7-3 | [DEBIAN-CVE-2026-15806](https://patchblox.com/security/data/fix/linux/debian-cve-2026-15806.md) | Sep 12, 2026 |
| Linux | python3.14 amzn 2023 | 3.14.8-1.amzn2023.0.1 | [ALAS2023-2026-3232](https://patchblox.com/security/data/fix/linux/alas2023-2026-3232.md) | Nov 7, 2026 |
| Linux | python3.14-debug amzn 2023 | 3.14.8-1.amzn2023.0.1 | [ALAS2023-2026-3232](https://patchblox.com/security/data/fix/linux/alas2023-2026-3232.md) | Nov 7, 2026 |
| Linux | python3.14-debuginfo amzn 2023 | 3.14.8-1.amzn2023.0.1 | [ALAS2023-2026-3232](https://patchblox.com/security/data/fix/linux/alas2023-2026-3232.md) | Nov 7, 2026 |
| Linux | python3.14-debugsource amzn 2023 | 3.14.8-1.amzn2023.0.1 | [ALAS2023-2026-3232](https://patchblox.com/security/data/fix/linux/alas2023-2026-3232.md) | Nov 7, 2026 |
| Linux | python3.14-devel amzn 2023 | 3.14.8-1.amzn2023.0.1 | [ALAS2023-2026-3232](https://patchblox.com/security/data/fix/linux/alas2023-2026-3232.md) | Nov 7, 2026 |
| Linux | python3.14-freethreading amzn 2023 | 3.14.8-1.amzn2023.0.1 | [ALAS2023-2026-3232](https://patchblox.com/security/data/fix/linux/alas2023-2026-3232.md) | Nov 7, 2026 |
| Linux | python3.14-freethreading-debug amzn 2023 | 3.14.8-1.amzn2023.0.1 | [ALAS2023-2026-3232](https://patchblox.com/security/data/fix/linux/alas2023-2026-3232.md) | Nov 7, 2026 |
| Linux | python3.14-freethreading-devel amzn 2023 | 3.14.8-1.amzn2023.0.1 | [ALAS2023-2026-3232](https://patchblox.com/security/data/fix/linux/alas2023-2026-3232.md) | Nov 7, 2026 |
| Linux | python3.14-freethreading-idle amzn 2023 | 3.14.8-1.amzn2023.0.1 | [ALAS2023-2026-3232](https://patchblox.com/security/data/fix/linux/alas2023-2026-3232.md) | Nov 7, 2026 |
| Linux | python3.14-freethreading-libs amzn 2023 | 3.14.8-1.amzn2023.0.1 | [ALAS2023-2026-3232](https://patchblox.com/security/data/fix/linux/alas2023-2026-3232.md) | Nov 7, 2026 |
| Linux | python3.14-freethreading-test amzn 2023 | 3.14.8-1.amzn2023.0.1 | [ALAS2023-2026-3232](https://patchblox.com/security/data/fix/linux/alas2023-2026-3232.md) | Nov 7, 2026 |
| Linux | python3.14-freethreading-tkinter amzn 2023 | 3.14.8-1.amzn2023.0.1 | [ALAS2023-2026-3232](https://patchblox.com/security/data/fix/linux/alas2023-2026-3232.md) | Nov 7, 2026 |
| Linux | python3.14-idle amzn 2023 | 3.14.8-1.amzn2023.0.1 | [ALAS2023-2026-3232](https://patchblox.com/security/data/fix/linux/alas2023-2026-3232.md) | Nov 7, 2026 |
| Linux | python3.14-libs amzn 2023 | 3.14.8-1.amzn2023.0.1 | [ALAS2023-2026-3232](https://patchblox.com/security/data/fix/linux/alas2023-2026-3232.md) | Nov 7, 2026 |
| Linux | python3.14-test amzn 2023 | 3.14.8-1.amzn2023.0.1 | [ALAS2023-2026-3232](https://patchblox.com/security/data/fix/linux/alas2023-2026-3232.md) | Nov 7, 2026 |
| Linux | python3.14-tkinter amzn 2023 | 3.14.8-1.amzn2023.0.1 | [ALAS2023-2026-3232](https://patchblox.com/security/data/fix/linux/alas2023-2026-3232.md) | Nov 7, 2026 |
| Linux | python3.15 Debian 14 | 3.15.0~rc2-1 | [DEBIAN-CVE-2026-15806](https://patchblox.com/security/data/fix/linux/debian-cve-2026-15806.md) | Sep 12, 2026 |
| Linux | python311 sles 15.6 | 3.11.17-150600.3.74.1 | [SUSE-SU-2026:4946-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-4946-1.md) | Nov 7, 2026 |
| Linux | python311 sles 15.7 | 3.11.17-150600.3.74.1 | [SUSE-SU-2026:4946-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-4946-1.md) | Nov 7, 2026 |
| Linux | python311-core sles 15.6 | 3.11.17-150600.3.74.1 | [SUSE-SU-2026:4946-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-4946-1.md) | Nov 7, 2026 |
| Linux | python311-core sles 15.7 | 3.11.17-150600.3.74.1 | [SUSE-SU-2026:4946-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-4946-1.md) | Nov 7, 2026 |
| Linux | python312 sles 15.6 | 3.12.14-150600.3.68.1 | [SUSE-SU-2026:4534-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-4534-1.md) | Oct 6, 2026 |
| Linux | python312-core sles 15.6 | 3.12.14-150600.3.68.1 | [SUSE-SU-2026:4534-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-4534-1.md) | Oct 6, 2026 |
| Linux | python313 sles 15.7 | 3.13.16-150700.4.61.1 | [SUSE-SU-2026:4941-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-4941-1.md) | Nov 7, 2026 |
| Linux | python313-core sles 15.7 | 3.13.16-150700.4.61.1 | [SUSE-SU-2026:4941-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-4941-1.md) | Nov 7, 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 2026-11-09T07:25:28Z 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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