Malicious PDF — malware analysis report

Static analysis result for SHA-256 4dc91f031c72d215…

MALICIOUS

PDF

47.2 KB Created: 2020-09-03 00:18:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e30b4a4dcf889e807b1ea2a4ef7209b9 SHA-1: 4acac81d6e01ada74c432fea8cc3debee4596589 SHA-256: 4dc91f031c72d2155eed530d8717aad1407d1558ec1304f018bed6f74ac5b5d4
154 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, many of which point to other PDF files hosted on various platforms, suggesting a link farm for SEO manipulation or to obscure malicious activity. One of these links redirects to a known malicious URL, indicating a potential phishing or malware distribution attempt. The ML classifier also strongly flagged this PDF as malicious.

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=android+studio+install+performance%2528+intel+haxm%2529
    • https://cdn.shopify.com/s/files/1/0428/2174/6847/files/45450211706.pdf
    • https://cdn.shopify.com/s/files/1/0435/1531/4330/files/finizenupov.pdf
    • https://cdn.shopify.com/s/files/1/0433/6071/4904/files/jiropejutexukes.pdf
    • https://static.usrfiles.com/ugd/111c46_d4fe83c886534040996beb5f91ffda9c.pdf
    • https://static.usrfiles.com/ugd/0a593f_59dea0ad2a964b97a42c4b432fa8f6b7.pdf
    • https://cdn.shopify.com/s/files/1/0464/0948/2408/files/francis_bacon_essays_of_studies.pdf
    • https://cdn.shopify.com/s/files/1/0434/8405/3669/files/29069589054.pdf
    • https://cdn.shopify.com/s/files/1/0435/4444/5092/files/little_piggy_song.pdf
    • https://cdn.shopify.com/s/files/1/0437/0766/2504/files/matodakowa.pdf
    • https://static.usrfiles.com/ugd/f1780b_96436e27d64b4c03aaa6de65855cb94c.pdf
    • https://static.usrfiles.com/ugd/11baf9_bd4770f0b43346969611a4db1c8847a8.pdf
    • https://static.usrfiles.com/ugd/52b593_3e872e410ad449ebad7840d3b7dedcdd.pdf
    • https://static.usrfiles.com/ugd/3ceeb9_e9b91a7dab79448a9d48d54c4629d560.pdf
    • https://static.usrfiles.com/ugd/8b97dd_3c82e71b7ebc44da8b21d91bb1578def.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_off000075c0.bin
2926d26bfa9a0f25f1e6429ffd2945deaeb0f8bda79c4dfacc0e5612b1d2ea91
pdf-font-stream PDF embedded font (sfnt) at offset 0x75C0 5604 bytes
font_01_sfnt_off000088bb.bin
3699606e820dccf9476adc57fa7c5f26e7c63dc02898b534246020f78bef9e48
pdf-font-stream PDF embedded font (sfnt) at offset 0x88BB 11992 bytes