Malicious PDF — malware analysis report

Static analysis result for SHA-256 dc9633ba81f520f7…

MALICIOUS

PDF

41.5 KB Created: 2020-08-21 07:43:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f59dc10fc15b103e8c6e88f342d60f39 SHA-1: c3d378a2f2b3a9c91ed8e0869ec0588fcbf2cc2d SHA-256: dc9633ba81f520f7e7a28aa903508acff6c583cc4acce994e554dbb6decc29ce
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell

The PDF contains numerous embedded links, with one specifically pointing to a known malicious redirector. The document body text, though garbled, contains the phrase 'free chess books online' and the malicious URL, suggesting a lure to a phishing or malware distribution site. The ML classifier strongly indicates maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://ttraff.ru/pify?keyword=free+chess+books+online
    • http://files.specialblessingschildcare.com/uploads/1/3/0/8/130874432/movivuwen.pdf
    • http://tuwaruzu.golfeuropeexperience.com/uploads/1/3/1/4/131410812/fba60fa3ec3.pdf
    • http://wakuxoru.npsracing.com/uploads/1/3/1/6/131607131/1ed9fee3e9a20.pdf
    • http://files.ncwknittersguild.com/uploads/1/3/1/0/131070713/besodeta_mesokewalemo_basedemu_jipifonovabefes.pdf
    • https://cdn.shopify.com/s/files/1/0435/9133/6099/files/escala_de_barthel_para_imprimir.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/11783771814.pdf
    • https://cdn.shopify.com/s/files/1/0429/5265/5004/files/kedokavogilasepapu.pdf
    • https://cdn.shopify.com/s/files/1/0433/5442/3464/files/ponaralavokizibejaz.pdf
    • https://cdn.shopify.com/s/files/1/0431/7826/2692/files/dasefaze.pdf
    • https://cdn.shopify.com/s/files/1/0439/1328/1688/files/nunuk.pdf
    • https://cdn.shopify.com/s/files/1/0431/5535/7858/files/komib.pdf
    • https://cdn.shopify.com/s/files/1/0430/9037/8901/files/86773764602.pdf
    • https://cdn.shopify.com/s/files/1/0437/0923/5355/files/minority_report_film_imdb.pdf
    • https://cdn.shopify.com/s/files/1/0436/2698/7680/files/zibivelizusivefekatem.pdf
    • https://cdn.shopify.com/s/files/1/0429/0743/5167/files/wipasufan.pdf
    • https://cdn.shopify.com/s/files/1/0431/1013/8017/files/88813214988.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00006565.bin
cd0cf3363d29700f6c29099d7a6e9e7b1702e9db295ddd160c6beac0d2c4cc1e
pdf-font-stream PDF embedded font (sfnt) at offset 0x6565 4836 bytes
font_01_sfnt_off000075cc.bin
175fcd6b85813021655a1f8765843426a2b992361431f4eb5aa8b1a615fdbc3a
pdf-font-stream PDF embedded font (sfnt) at offset 0x75CC 10444 bytes