OESA-2026-2660

A high-level Python Web framework that encourages rapid development and clean, pragmatic design.

Security Fix(es):

An issue was discovered in Django 5.2 before 5.2.15 and 6.0 before 6.0.6. django.middleware.cache.UpdateCacheMiddleware in Django does not add Authorization to the Vary response header for requests bearing that header without Cache-Control: public, which allows remote attackers to read private cached responses via unauthenticated requests to the same URL. 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 Shai Berger for reporting this issue.(CVE-2026-35193)

An issue was discovered in Django 5.2 before 5.2.15 and 6.0 before 6.0.6. django.utils.cache.has_vary_header() in Django does not strip leading or trailing whitespace from Vary response header values before comparison, which allows remote attackers to read cached responses via requests to URLs whose responses contain whitespace-padded Vary header values. 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 Navid Rezazadeh for reporting this issue.(CVE-2026-48587)

An issue was discovered in Django 6.0 before 6.0.6 and 5.2 before 5.2.15. django.http.HttpRequest.get_signed_cookie in Django uses a non-injective salt derivation (concatenating the cookie name and salt argument), which allows a remote attacker to use a cookie in a context different from the one where it was signed, via distinct (name, salt) pairs that produce the same concatenation. 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 Peng Zhou for reporting this issue.(CVE-2026-6873)

An issue was discovered in Django 6.0 before 6.0.6 and 5.2 before 5.2.15. django.core.mail.backends.smtp.EmailBackend in Django fails to prevent reuse of a partially-initialized connection after a failed STARTTLS handshake when fail_silently=True, which allows on-path network attackers to read email content via cleartext interception. 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 Kasper Dupont for reporting this issue.(CVE-2026-7666)

An issue was discovered in Django 5.2 before 5.2.15 and 6.0 before 6.0.6. django.middleware.cache.UpdateCacheMiddleware in Django does not match Cache-Control response directives case-insensitively, which allows remote attackers to read responses that were incorrectly cached because their Cache-Control directives used uppercase or mixed-case values. 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 Ahmed Badawe for reporting this issue.(CVE-2026-8404)