CVE intelligence and bounded remediation
CVE-2026-53961 — Discourse is an open-source discussion platform
Discourse is an open-source discussion platform. Prior to 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5, the AWS SES bounce webhook at POST /webhooks/aws verified that SNS messages were signed by Amazon but did not bind them to trusted TopicArn values, allowing any AWS account holder to publish validly signed forged Bounce notifications that revoke a targeted user email. This issue is fixed in versions 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5.
- Severity
- Medium
- CVSS
- 6.5 (3.1)
- Published
- 2026-07-09
- CISA KEV
- Not currently listed
- Ecosystem
- software/application
- Weaknesses
- CWE-345
Affected products
- discourse / discourse
- discourse / discourse / 2026.6.0
Matched remediation archetype
Supply-chain, dependency, build, and update integrity
This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.
Check exposure
- Trace affected packages, source archives, build actions, plugins, installers, and updates from declared source to deployed artifact.
- Confirm provenance, signatures or digests, namespace ownership, lockfile resolution, registry configuration, and build-runner trust boundaries.
- Inventory direct, transitive, vendored, generated, and bundled copies across releases and distribution channels.
Remediate safely
- Move to a maintained trusted artifact or remove the dependency; pin immutable identities and verify provenance and integrity before use.
- Regenerate lockfiles and artifacts in a clean isolated build, minimize build credentials and network access, and produce an updated software bill of materials.
- Require reviewed update policy, protected publishing, and reproducible or independently attestable builds where supported.
Authoritative sources
Complete CVE record and remediation plan
The detailed catalog view below loads this exact record, its source evidence, and the full seven-phase agentic change plan.