What's Changed

• fix: Correct schema false positives for ElastiCache and IAM by @kddejong in #4540
• chore(deps): bump codecov/codecov-action from 6 to 7 by @dependabot[bot] in #4541
• fix: Allow decimal values in Logs MetricFilter MetricValue pattern by @kddejong in #4542
• Update CloudFormation schemas to 2026-06-12 by @github-actions[bot] in #4538
• fix: Make EC2::TrafficMirrorFilterRule TrafficDirection case-insensitive by @kddejong in #4543
• Update CloudFormation schemas to 2026-06-15 by @github-actions[bot] in #4544

Full Changelog: v1.51.4...v1.51.5

What's Changed

• fix: E3042 false positive when Essential is omitted from ECS containers by @kddejong in #4536
• Update CloudFormation schemas to 2026-06-03 by @github-actions[bot] in #4534

Full Changelog: v1.51.3...v1.51.4

What's Changed

• fix: Allow ProvisionedThroughput with 0 values when BillingMode is PAY_PER_REQUEST by @kddejong in #4524
• Revert: S3 bucket names with uppercase should remain an error by @kddejong in #4528
• fix: Allow ARN format for Lambda FunctionName property by @kddejong in #4529
• feat: Add OpenSearch instance type validation from pricing API by @kddejong in #4525
• fix: Sync update_schemas_manually.py with committed manual.json files by @kddejong in #4530
• Update CloudFormation schemas to 2026-06-02 by @github-actions[bot] in #4523
• fix: Update Lambda runtime lifecycle dates from AWS docs by @kddejong in #4532

Full Changelog: v1.51.2...v1.51.3

What's Changed

• fix: Allow Fn::GetStackOutput in Output Values, Fn::Sub, and Fn::Base64 by @kddejong in #4519
• feat: Add rule E3065 for maxUniqueItems validation by @kddejong in #4520
• Update CloudFormation schemas to 2026-05-27 by @github-actions[bot] in #4518
• fix: Support additional functions inside Fn::GetAZs by @kddejong in #4521

Full Changelog: v1.51.1...v1.51.2

What's Changed

• Fix Ref and GetAtt validation for MODULE sub-resources by @kddejong in #4510
• Fix TypeError in PipelineArtifactCounts when Provider is a Ref by @kddejong in #4512
• Update CloudFormation schemas to 2026-05-18 by @github-actions[bot] in #4509
• chore(deps): bump pyinstaller from 6.19.0 to 6.20.0 in /requirements by @dependabot[bot] in #4500
• chore(deps): update pyyaml requirement from >5.4 to >=6.0.3 in /requirements by @dependabot[bot] in #4471
• chore(deps): update aws-sam-translator requirement from >=1.109.0 to >=1.110.0 in /requirements by @dependabot[bot] in #4515
• Update CloudFormation schemas to 2026-05-21 by @github-actions[bot] in #4513
• Allow uppercase S3 bucket names, warn instead of error by @kddejong in #4516

Full Changelog: v1.51.0...v1.51.1

What's Changed

• Update snapshots script and conditions yaml by @satyakigh in #4479
• feat: add rule W1054 to warn on raw pseudo-parameter strings without Ref by @cv-dote in #4453
• feat: add rule E3064 to validate duplicate Interface VPC Endpoint with PrivateDnsEnabled by @kddejong in #4492
• feat: Add support for Fn::GetStackOutput intrinsic function by @kddejong in #4495
• Fix E3039 crash when Fn::Transform used at list properties by @kddejong in #4498
• Fix ResultWriter schema of step functions by @szbartnik in #4497
• Update CloudFormation schemas to 2026-05-11 by @github-actions[bot] in #4490
• Move SSM Parameter Name prefix check from error to warning by @kddejong in #4501
• Fix W3664 false positive for regional CWL principal by @kddejong in #4506
• Fix schema validation issues and add warning rules by @kddejong in #4502
• Update CloudFormation schemas to 2026-05-12 by @github-actions[bot] in #4503
• Include usage path in W3034 parameter range error by @kddejong in #4507

New Contributors

• @satyakigh made their first contribution in #4479
• @cv-dote made their first contribution in #4453
• @szbartnik made their first contribution in #4497

Full Changelog: v1.50.1...v1.51.0

What's Changed

• fix: Rule E3031 false positive for boolean values with pattern by @kddejong in #4485
• Add python 3.14 support by @kddejong in #4487
• Update CloudFormation schemas to 2026-04-29 by @github-actions[bot] in #4483
• fix: use TOML-native posargs syntax for multi-arg expansion by @kddejong in #4488

Full Changelog: v1.50.0...v1.50.1

What's Changed

• feat: add rule E3720 to validate StorageEncrypted is set when KmsKeyId is specified for non-custom engine RDS DBInstances by @kddejong in #4480
• feat: add rule E3721 to validate ReplicaMode enum values for Oracle and Db2 engines by @kddejong in #4480
• feat: add rule W3699 to warn when ReplicaMode is specified for non-Oracle/Db2 engines (silently ignored) by @kddejong in #4480
• feat: add rule W3700 to warn when EIP Domain has non-standard values (silently converted to vpc) by @kddejong in #4480
• Add maxUniqueItems JSON Schema keyword for arrays where duplicates are allowed but unique count is limited by @kddejong in #4480
• Fix schema validation false positives for CloudWatch Alarm actions, Lambda Layers, Connect RoutingProfile, and stale smithy enums by @kddejong in #4480
• Update CI badge in README.md by @ScottBrenner in #4478
• Update CloudFormation schemas to 2026-04-27 by @github-actions[bot] in #4477

Full Changelog: v1.49.3...v1.50.0

What's Changed

• chore(deps): update sympy requirement from >=1.0.0 to >=1.14.0 in /requirements by @dependabot[bot] in #4473
• Fix E3719 false positive when BackupRetentionPeriod is omitted by @kddejong in #4475
• Update CloudFormation schemas to 2026-04-22 by @github-actions[bot] in #4467

Full Changelog: v1.49.2...v1.49.3

What's Changed

• Fix E1041 false positive: add Lambda::Function.Arn format to Lambda Alias by @kddejong in #4469

Full Changelog: v1.49.1...v1.49.2