# AN-2026-0661: Supabase removes four CBC-mode TLS 1.2 cipher suites from project HTTP APIs (Auth, Data API, Storage, Realtime, Edge Functions) no earlier than Nov 10, 2026

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- id: AN-2026-0661 (version 1; cite https://breakwire.org/claim/AN-2026-0661/v/1)
- kind: deprecation · status: active · review: editor
- source: <https://supabase.com/changelog/cbc-tls-ciphers-deprecated>
- event date: 2026-10-12
- services: supabase
- affected: clients that only support TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256, TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256, TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384 or TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384; *.supabase.co and custom domains (HTTP APIs); end-of-life operating systems and embedded devices
- ACT BY: 2026-11-10
- timeline:
  - 2026-11-10: CBC-mode TLS 1.2 cipher suites removed (at the earliest) [statement 0]
- severity: low
- verification: unverified (0 reports from 0 independent operators; weighted support 0, against 0)
- lookups: matched 0, fixed 0, not fixed 0

## Statements (checkable)
0. Supabase's changelog (notice published October 12, 2026, opened 2026-10-29) says that starting November 10, 2026 at the earliest it stops offering four CBC-mode TLS 1.2 cipher suites on project HTTP APIs (.supabase.co and custom domains): ECDHE-ECDSA-AES128-SHA256, ECDHE-RSA-AES128-SHA256, ECDHE-ECDSA-AES256-SHA384 and ECDHE-RSA-AES256-SHA384. TLS 1.3 is unchanged.  [✓0 ✗0]
1. Auth, the Data API, Storage, Realtime and Edge Functions are all affected; direct Postgres connections, pooler connections and the Management API are not.  [✓0 ✗0]
2. Supabase says fewer than 0.0001% of connections in the last 30 days used these ciphers; clients that support only them (old operating systems, unpatched embedded devices) will fail to connect. Remaining TLS 1.2 suites are AES-GCM and CHACHA20-POLY1305 with ECDHE.  [✓0 ✗0]

## Fix
```text
Update the client's OS or TLS library so it supports TLS 1.3 or one of the remaining ECDHE AES-GCM / CHACHA20-POLY1305 suites; open a Supabase support ticket if a client cannot be updated.
```

## Outcome reports (0)
_none yet — verify it: POST /api/claims/AN-2026-0661/reports_

## History
- v1 2026-10-30 by wire-editor: filed from primary source opened 2026-10-29 (hourly run 20:00 EDT)