Malicious PDF — malware analysis report

Static analysis result for SHA-256 dfdeb490b7107948…

MALICIOUS

PDF

41.4 KB Created: 2020-08-16 13:44:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f6968866568effad507394c17a82be35 SHA-1: 50b521e4ffe4e979da6ee7a250c5805a31e3475d SHA-256: dfdeb490b71079488d978f1d7cb3fdcefe80702d5e33a5e520decc48d35b8291
152 Risk Score

Malware Insights

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

The PDF contains a critical heuristic firing for a malicious redirector link, specifically `https://ttraff.cc/pify?keyword=dog+song+undertale+piano+sheet+music`. This URL is presented within the document body, disguised as sheet music, to entice users to click. The PDF also exhibits characteristics of a link farm, with numerous embedded URLs pointing to external resources, many of which are hosted on Shopify. The ML classifier strongly indicated maliciousness. No scripts were extracted, but the primary attack vector appears to be social engineering via a deceptive link.

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=dog+song+undertale+piano+sheet+music
    • http://files.northwesternchristianwritersconference.com/uploads/1/3/0/7/130775368/nizujoz.pdf
    • https://cdn.shopify.com/s/files/1/0431/8789/6482/files/kotinikojulafot.pdf
    • https://cdn.shopify.com/s/files/1/0430/0262/6202/files/java_swing_notes.pdf
    • https://cdn.shopify.com/s/files/1/0434/0924/4317/files/33925024950.pdf
    • https://cdn.shopify.com/s/files/1/0428/3239/6447/files/pcat_practice_test.pdf
    • https://cdn.shopify.com/s/files/1/0429/5173/7498/files/counseling_assessment_and_evaluation.pdf
    • https://cdn.shopify.com/s/files/1/0431/0440/3613/files/73962293764.pdf
    • https://cdn.shopify.com/s/files/1/0431/6423/7992/files/36920598601.pdf
    • https://cdn.shopify.com/s/files/1/0431/6105/9482/files/gixesoradavewef.pdf
    • https://cdn.shopify.com/s/files/1/0436/7620/5209/files/59320915264.pdf
    • https://cdn.shopify.com/s/files/1/0430/5905/2706/files/c._p._c_bare_act.pdf
    • https://cdn.shopify.com/s/files/1/0432/5123/7032/files/2232803331.pdf
    • https://cdn.shopify.com/s/files/1/0429/9853/0202/files/motij.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_off00005900.bin
3620a23f34f446056bc474942fa2aed6ee57a2f5bc77325281a5dd61e91a43bd
pdf-font-stream PDF embedded font (sfnt) at offset 0x5900 5488 bytes
font_01_sfnt_off00006b7e.bin
954cdb414d07a8cf140585dbe08870b975c0c34cc48f7e48ee6c5ced07d39e37
pdf-font-stream PDF embedded font (sfnt) at offset 0x6B7E 14568 bytes