---
schema_version: "0.1.0"
type: gap
gap_id: "G-0001"
canonical_title: "Pages 1–6 of DOW-UAP-D54 are bit-for-bit identical (same SHA-256)"
gap_class: unexplained-redaction

description: |
  Pages 1, 2, 3, 4, 5, and 6 of the PDF `DOW-UAP-D54-Mission-Report-Mediterranean-
  Sea-NA.pdf` were converted to PNG at 200 DPI and produced six IDENTICAL files,
  all with SHA-256 `29030fd640030926c9e98e94f73a3fbc88cb9ac6739778b012eba120084ed1b7`.

  Visually, all six pages show the same image: solid black background (full-page
  redaction) with only the string "1.4(a)" in red at the top-left corner. The OCR
  (`pdftotext -layout`) of each page also produces only the text "1.4(a)".

  The most plausible hypothesis is that during the release process, six originally
  distinct pages (likely six different blocks of classified content) were ALL
  replaced by a single redaction template image, instead of each page having its
  own redaction overlay preserving sub-redacted structure.

description_pt_br: |
  As páginas 1, 2, 3, 4, 5 e 6 do PDF `DOW-UAP-D54-Mission-Report-Mediterranean-
  Sea-NA.pdf` foram convertidas em PNG @ 200 DPI e produziram seis arquivos
  IDÊNTICOS, todos com SHA-256 `29030fd640030926c9e98e94f73a3fbc88cb9ac6739778b012eba120084ed1b7`.

  Visualmente, as seis páginas mostram a mesma imagem: fundo preto sólido (redação
  de página inteira) com apenas a string "1.4(a)" em vermelho no canto superior
  esquerdo. O OCR (`pdftotext -layout`) de cada página produz apenas o texto "1.4(a)".

  A hipótese mais plausível é que durante o processo de liberação, seis páginas
  originalmente distintas (provavelmente seis blocos diferentes de conteúdo
  classificado) foram TODAS substituídas por uma única imagem-template de redação,
  em vez de cada página ter sua própria sobreposição preservando a estrutura
  sub-redatada.

detected_in:
  - "[[dow-uap-d54-mission-report-mediterranean-sea-na/p001]]"
  - "[[dow-uap-d54-mission-report-mediterranean-sea-na/p002]]"
  - "[[dow-uap-d54-mission-report-mediterranean-sea-na/p003]]"
  - "[[dow-uap-d54-mission-report-mediterranean-sea-na/p004]]"
  - "[[dow-uap-d54-mission-report-mediterranean-sea-na/p005]]"
  - "[[dow-uap-d54-mission-report-mediterranean-sea-na/p006]]"
detected_by: archivist
detected_at: "2026-05-13T08:50:00Z"

severity: medium
investigative_impact: |
  Substitution by an identical template erases any residual visual structure
  (margins, headers, paragraph spacing, partial signature blocks) that might
  permit inference about the redacted content. This compromises forensic
  analysis of redaction patterns. For other documents in the corpus with
  partial redactions, it is possible to roughly infer the size/position of
  removed text — here that is impossible.
investigative_impact_pt_br: |
  A substituição por template idêntico apaga qualquer estrutura visual residual
  (margens, cabeçalhos, espaçamento de parágrafos, blocos parciais de assinatura)
  que poderia permitir inferência sobre o conteúdo redatado. Compromete a análise
  forense de padrões de redação. Para outros documentos do corpus com redações
  parciais é possível inferir aproximadamente o tamanho/posição do texto
  removido — aqui isso é impossível.

possible_explanations:
  - { explanation: "Redaction template applied in bulk for all SECRET-classified pages", confidence_band: medium }
  - { explanation: "Bug in release/redaction software that duplicated a single page image", confidence_band: low }
  - { explanation: "Deliberate decision to uniform the appearance of fully redacted pages", confidence_band: medium }

recommended_actions:
  - "Cross-check other documents in the DOW-UAP-D series to see if the pattern repeats"
  - "Compare PDF metadata (xref, font subsetting, image XObject ids) between the 6 pages"
  - "Check whether other corpus PDFs with all-redacted pages exhibit the same SHA collision"

related_gaps: ["[[gap/G-0002]]"]
wiki_version: "0.1.0"
---

# Gap G-0001 — Identical pages in DOW-UAP-D54

Anomaly detected via SHA-256 collision across 6 PNGs derived from 6 distinct pages of the original PDF. See `description` / `description_pt_br` in frontmatter.
