{
  "variant_id": "CVE-2026-5479-variant-attempt",
  "created_at": "2026-05-28T12:00:00Z",
  "variant_summary": "Systematic variant attempts against wolfSSL EVP ChaCha20-Poly1305 tag verification fix. Three distinct variants tested: (1) EVP_CipherInit streaming path, (2) modified AAD with correct tag, (3) flipped ciphertext byte with correct tag. None reproduced on fixed version.",
  "relation": "newer_version_sibling",
  "origin_kind": "pruva_variant",
  "repository": "https://github.com/wolfSSL/wolfssl",
  "submitted_target": {
    "target_kind": "git_tag",
    "version": "v5.9.0-stable",
    "commit_sha": "922d04b3568c6428a9fb905ddee3ef5a68db3108",
    "display": "v5.9.0-stable (922d04b3)"
  },
  "variant_target": {
    "target_kind": "git_tag",
    "version": "v5.9.1-stable",
    "commit_sha": "1d363f3adceba9d1478230ede476a37b0dcdef24",
    "display": "v5.9.1-stable (1d363f3a)"
  },
  "same_root_cause_confidence": "high",
  "same_surface_confidence": "high",
  "claimed_surface": "wolfSSL_EVP_CipherFinal WC_CHACHA20_POLY1305_TYPE decrypt path",
  "validated_surface": "wolfSSL_EVP_CipherFinal WC_CHACHA20_POLY1305_TYPE decrypt path",
  "required_entrypoint_kind": "api_function",
  "required_entrypoint_detail": "EVP_CipherInit/EVP_CipherUpdate/EVP_CipherFinal or EVP_DecryptInit_ex/EVP_DecryptUpdate/EVP_DecryptFinal_ex with EVP_chacha20_poly1305()",
  "attacker_controlled_input": "ciphertext, authentication tag, AAD",
  "trigger_path": "wolfcrypt/src/evp.c:wolfSSL_EVP_CipherFinal -> WC_CHACHA20_POLY1305_TYPE branch",
  "observed_impact_class": "integrity_bypass",
  "exploitability_confidence": "high",
  "evidence_scope": "no_bypass_found",
  "runtime_manifest_present": false,
  "end_to_end_target_reached": true,
  "inferred": false,
  "file_path": "wolfcrypt/src/evp.c",
  "line_start": 1501,
  "line_end": 1538,
  "secondary_anchors": [
    {
      "file_path": "wolfcrypt/src/chacha20_poly1305.c",
      "line_start": 270,
      "line_end": 320
    },
    {
      "file_path": "src/quic.c",
      "line_start": 1370,
      "line_end": 1378
    }
  ],
  "review_scope_paths": [
    "wolfcrypt/src/evp.c",
    "wolfcrypt/src/chacha20_poly1305.c",
    "src/quic.c"
  ],
  "artifact_refs": {
    "variant_manifest": "vuln_variant/variant_manifest.json",
    "validation_verdict": "vuln_variant/validation_verdict.json",
    "repro_log": "logs/variant_vuln_output.txt",
    "reproducer": ["vuln_variant/reproduction_steps.sh", "vuln_variant/variant_test.c"]
  }
}