Description
An issue was discovered in 6.0 before 6.0.3, 5.2 before 5.2.12, and 4.2 before 4.2.29.
`URLField.to_python()` in Django calls `urllib.parse.urlsplit()`, which performs NFKC normalization on Windows that is disproportionately slow for certain Unicode characters, allowing a remote attacker to cause denial of service via large URL inputs containing these characters.
Earlier, unsupported Django series (such as 5.0.x, 4.1.x, and 3.2.x) were not evaluated and may also be affected.
Django would like to thank Seokchan Yoon for reporting this issue.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| djangoproject | Django | 6.0 – < 6.0.3, 5.2 – < 5.2.12, 4.2 – < 4.2.29 | 6.0.3 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.23 | py3-django | 4.2.29-r0 | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| PyPI | django | >= 6.0, < 6.0.3 | 6.0.3 | GHSA-8p8v-wh79-9r56 |
| PyPI | django | >= 5.2, < 5.2.12 | 5.2.12 | GHSA-8p8v-wh79-9r56 |
| PyPI | django | >= 4.2, < 4.2.29 | 4.2.29 | GHSA-8p8v-wh79-9r56 |
| PyPI | django | >= 4.2, < 4.2.29 · >= 5.2, < 5.2.12 · >= 6.0, < 6.0.3 | 4.2.29, 5.2.12, 6.0.3 | PYSEC-2026-2448 |
Advisories 3
- WID-SEC-2026-2933 Splunk SOAR: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 2, 2026
- WID-SEC-2026-1730 Xerox FreeFlow Print Server: Mehrere Schwachstellen ermöglichen nicht spezifizierten Angriff BSI CERT-Bund (WID) · Jul 16, 2026
- WID-SEC-2026-0579 Django: Mehrere Schwachstellen BSI CERT-Bund (WID) · Jun 7, 2026
References
- Django security archive vendor-advisory
- Django releases announcements mailing-list
- Django security releases issued: 6.0.3, 5.2.12, and 4.2.29 vendor-advisory