Malicious PDF — malware analysis report

Static analysis result for SHA-256 7951cde5c38b4d86…

MALICIOUS

PDF

35.7 KB Created: 2020-08-07 06:45:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: a8c52821dcc7e91119027c014ca995cc SHA-1: 725b04f0d7d26be33ec13e9c0cd7af26db8c9d3d SHA-256: 7951cde5c38b4d86e90216cb278191396355f7db7b82311849220d0177297eef
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous embedded links, with one pointing to a known malicious redirector. The document body, though heavily obfuscated, contains text and URLs that suggest a lure related to medical information to entice users to click on malicious links. The ML classifier strongly indicated maliciousness, supporting the presence of a malicious redirector.

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=absceso+hepatico+pdf+pediatria
    • http://files.boardroomdevelopment.com/uploads/1/3/0/7/130776590/xudowapisinelidiruwi.pdf
    • http://files.teachthewaytheylearn.net/uploads/1/3/1/4/131483154/187887.pdf
    • http://files.realjackoftrades.com/uploads/1/3/0/8/130874050/4800150.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0429/2627/6775/files/zuzefisegotikejokaxonet.pdf
    • https://cdn.shopify.com/s/files/1/0432/9078/8000/files/81077365339.pdf
    • https://cdn.shopify.com/s/files/1/0431/6754/7546/files/ophelia_piano_sheet_music.pdf
    • https://cdn.shopify.com/s/files/1/0432/5277/7128/files/92767063768.pdf
    • https://cdn.shopify.com/s/files/1/0428/4078/5062/files/60461296753.pdf
    • https://cdn.shopify.com/s/files/1/0439/7596/6878/files/motokowenuwokenowatopajuj.pdf
    • https://cdn.shopify.com/s/files/1/0429/5278/6074/files/96354975617.pdf
    • https://cdn.shopify.com/s/files/1/0433/4593/6534/files/target_return_policy_without_receipt_2016.pdf
    • https://cdn.shopify.com/s/files/1/0431/2809/4882/files/rixiripumipipojibofixina.pdf
    • https://cdn.shopify.com/s/files/1/0429/0481/3721/files/felegib.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/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00004e34.bin
3a83b9ce3a7fa3831562bc15febfc9ab793bfb27754c608c0f27475dd5c260f0
pdf-font-stream PDF embedded font (sfnt) at offset 0x4E34 5340 bytes
font_01_sfnt_off00006050.bin
7f5c46ef5313cddf7702c8e2565107c8cbef0cd9ffcafb18ffc8226b9dc3e0aa
pdf-font-stream PDF embedded font (sfnt) at offset 0x6050 9944 bytes