Malicious PDF — malware analysis report

Static analysis result for SHA-256 43855b3d4d03e21c…

MALICIOUS

PDF

36.4 KB Created: 2020-08-16 20:15:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f5d27428b04fa9575c337b32ac3b6c5e SHA-1: 29a649f0eef9c2fa8df2760621353b832da156a5 SHA-256: 43855b3d4d03e21c89afe5b7834b58e45c655c36b05a3311c81cbcf5a85e1300
152 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded links, characteristic of a link farm. One of these links, https://ttraff.cc/pify?keyword=budget+speech+2019+pdf+zambia, points to a known malicious redirector. The ML classifier also strongly indicated maliciousness. The document body appears to be corrupted or obfuscated, but the presence of the malicious redirector URL is sufficient to classify this as a malicious document.

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.cc/pify?keyword=budget+speech+2019+pdf+zambia
    • http://files.billysbearfootcruises.com/uploads/1/3/0/7/130739697/gomidirapogazoluwitu.pdf
    • https://cdn.shopify.com/s/files/1/0431/2262/2621/files/po_box_number_format.pdf
    • https://cdn.shopify.com/s/files/1/0432/6037/9286/files/ryan_aerator_parts.pdf
    • https://cdn.shopify.com/s/files/1/0433/7529/6677/files/american_music_awards_2018_performers_live.pdf
    • https://cdn.shopify.com/s/files/1/0431/7321/6412/files/kefigu.pdf
    • https://cdn.shopify.com/s/files/1/0434/7658/2550/files/82568814844.pdf
    • https://cdn.shopify.com/s/files/1/0430/2569/4883/files/88388299862.pdf
    • https://cdn.shopify.com/s/files/1/0433/1018/6654/files/83116934975.pdf
    • https://cdn.shopify.com/s/files/1/0440/7951/3752/files/fonegonezuvaxosubog.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/tekutuni.pdf
    • https://cdn.shopify.com/s/files/1/0433/4052/9816/files/44808177220.pdf
    • https://cdn.shopify.com/s/files/1/0428/5123/8047/files/pdf_to_word_converter_download_adobe.pdf
    • https://cdn.shopify.com/s/files/1/0432/1509/3917/files/88309963071.pdf
    • https://cdn.shopify.com/s/files/1/0431/0358/4413/files/59891340900.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_off00004a94.bin
35e0ada72697e789b54da405771e64dde9ed99a640d960897d70b103f32274fa
pdf-font-stream PDF embedded font (sfnt) at offset 0x4A94 6160 bytes
font_01_sfnt_off00005f81.bin
2569e3db7dddc5c7a364e3385f608e5b437c97a6b496d45b485381d341caa287
pdf-font-stream PDF embedded font (sfnt) at offset 0x5F81 10508 bytes