Malicious PDF — malware analysis report

Static analysis result for SHA-256 4d121ccb9047e8ff…

MALICIOUS

PDF

39.5 KB Created: 2020-08-23 12:30:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f8e065bae6ebed402f61ead8a3f709c3 SHA-1: 53becfab7f89ab6672ba31dec599a4a3e180e247 SHA-256: 4d121ccb9047e8ff6d71a5f6ec18a637f9f683b0574d18dd4fb70588021ebeaa
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious Link

The PDF document exhibits malicious characteristics, primarily through its extensive use of a link farm. The heuristic 'PDF_MALICIOUS_REDIRECTOR_LINK' indicates a direct link to known malicious redirector infrastructure, specifically 'https://ttraff.com/pify?keyword=marriage+anniversary+short+video'. Additionally, the 'PDF_SEO_LINK_FARM' heuristic reveals a large number of external PDF links, many hosted on 'cdn.shopify.com', suggesting an attempt to manipulate search engine results or distribute content through a wide network of seemingly benign URLs. The ML classifier also strongly flagged this PDF as malicious. No scripts were extracted, but the structure and embedded links point towards a delivery mechanism for malicious content.

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.com/pify?keyword=marriage+anniversary+short+video
    • http://files.itinerantliteratebooks.com/uploads/1/3/1/8/131856188/0dd02b87.pdf
    • https://cdn.shopify.com/s/files/1/0430/1943/6185/files/32433913300.pdf
    • https://cdn.shopify.com/s/files/1/0428/6542/6598/files/37044324624.pdf
    • https://cdn.shopify.com/s/files/1/0440/2518/4421/files/votasodunokepunitoxaf.pdf
    • https://cdn.shopify.com/s/files/1/0428/5304/0295/files/4_3_under_defense_playbook.pdf
    • https://cdn.shopify.com/s/files/1/0440/2423/4149/files/trattoria_trattato_campoformido.pdf
    • https://cdn.shopify.com/s/files/1/0434/3480/3352/files/41929015419.pdf
    • https://cdn.shopify.com/s/files/1/0429/5802/8959/files/cnet_download_reader.pdf
    • https://cdn.shopify.com/s/files/1/0429/7061/1861/files/rudram_tamil.pdf
    • https://cdn.shopify.com/s/files/1/0437/2971/5354/files/the_reading_strategies_book_by_jennifer_serravallo.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/dijovosulodomozov.pdf
    • https://cdn.shopify.com/s/files/1/0433/4567/4389/files/delinibunoruxux.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_off00005e94.bin
3cf07056b187ceee11961f32d8b8547faf5e74eaedf39f5901c9dd8c0fe70c35
pdf-font-stream PDF embedded font (sfnt) at offset 0x5E94 5224 bytes
font_01_sfnt_off0000705a.bin
c760bb77cafed954e938fdc8d876f6f9d1824f67aa7a4e943db6a7a019d7d93c
pdf-font-stream PDF embedded font (sfnt) at offset 0x705A 9776 bytes