Malicious PDF — malware analysis report

Static analysis result for SHA-256 d4a50a0e4b216331…

MALICIOUS

PDF

36.1 KB Created: 2020-08-15 20:41:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e6b99a4ae342aabdc2267e48b4ef8737 SHA-1: 5741984a809ecd7a21bf0a67679f4b34fc41ae6a SHA-256: d4a50a0e4b216331cafdec94351b337e7c5ebf44a75550bd4e1ada78a67c44ee
154 Risk Score

Malware Insights

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

The PDF contains a heuristic firing for a malicious redirector link, pointing to 'https://ttraff.cc/pify?keyword=enzyme+structure+and+function+worksheet'. It also exhibits characteristics of a PDF link farm, with numerous embedded links, many hosted on Shopify. The document body, though heavily obfuscated, contains the same malicious URL and a benign-looking PDF filename, suggesting a lure for users to click the link. The ML classifier 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=enzyme+structure+and+function+worksheet
    • http://files.sfxfaithformation.org/uploads/1/3/2/8/132814286/7365526.pdf
    • http://vewoxuxo.larryphillipsnyc.com/uploads/1/3/0/8/130874246/408239421.pdf
    • https://cdn.shopify.com/s/files/1/0433/5471/8358/files/jejewego.pdf
    • https://cdn.shopify.com/s/files/1/0438/4561/5766/files/school_calendar_2020_rwanda.pdf
    • https://cdn.shopify.com/s/files/1/0428/0591/9903/files/tomudubelatevadowapep.pdf
    • https://cdn.shopify.com/s/files/1/0432/5667/6510/files/20076768361.pdf
    • https://cdn.shopify.com/s/files/1/0433/5288/3352/files/23281457691.pdf
    • https://cdn.shopify.com/s/files/1/0432/3698/2944/files/vagutajiwunadiguxusele.pdf
    • https://cdn.shopify.com/s/files/1/0428/9665/4489/files/bartholin_abscess_treatment.pdf
    • https://cdn.shopify.com/s/files/1/0435/1308/6106/files/botany_honours_syllabus_2020.pdf
    • https://cdn.shopify.com/s/files/1/0436/1935/2739/files/2d_animation_in_blender.pdf
    • https://cdn.shopify.com/s/files/1/0436/4979/4213/files/catholic_social_teaching_textbook_saint_mary_press.pdf
    • https://cdn.shopify.com/s/files/1/0437/6743/1320/files/amino_acids_proteins_and_peptides.pdf
    • https://cdn.shopify.com/s/files/1/0459/6996/5216/files/cakephp_form_helper_template.pdf
    • https://cdn.shopify.com/s/files/1/0428/8030/3270/files/suwofabepujowokujirine.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_off00004f09.bin
ddf6ad4db8ac92d0abb380d54685007b836ebdb40b9dbe5ae0fbb9d443a3a3f1
pdf-font-stream PDF embedded font (sfnt) at offset 0x4F09 5496 bytes
font_01_sfnt_off000061ab.bin
c1b5c69998aeb47cfd0d490e361b784f96f157c9d1998bbf3e179b227a9368bb
pdf-font-stream PDF embedded font (sfnt) at offset 0x61AB 9900 bytes