Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4cc2838607e6a05…

MALICIOUS

PDF

42.0 KB Created: 2020-08-09 11:36:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 27d46a7a6aad17c032628ca3a07a34f5 SHA-1: 8b54d09963589845187aeacd5e69107685184d10 SHA-256: c4cc2838607e6a055d535968220f8953f731f927487dc272f1ccc32674d96063
154 Risk Score

Malware Insights

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

The PDF contains a mass external link farm, with a primary malicious redirector URL embedded. The document body, though partially corrupted, includes the text 'Capitalization worksheets for grade 2 pdf' and the malicious URL, suggesting a lure to disguise the malicious intent. 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=capitalization+worksheets+for+grade+2+pdf
    • http://files.stpaulslewisburg.org/uploads/1/3/0/7/130776674/gapizopejunatux-bewodavov-lakiju-powukonosud.pdf
    • http://files.oxfordcitylionsfutsal.com/uploads/1/3/1/0/131070230/pufugavise.pdf
    • http://tipivele.cs-crawfordsolutions.com/uploads/1/3/2/7/132740892/354028f.pdf
    • http://files.alizarothdmt.com/uploads/1/3/0/8/130814296/b709c494300fc.pdf
    • http://gegoz.figureitin.org/uploads/1/3/0/8/130874524/169852314321.pdf
    • https://cdn.shopify.com/s/files/1/0432/6014/9910/files/96996670056.pdf
    • https://cdn.shopify.com/s/files/1/0430/0288/8351/files/32939626426.pdf
    • https://cdn.shopify.com/s/files/1/0438/3893/1109/files/84042481301.pdf
    • https://cdn.shopify.com/s/files/1/0437/9449/7698/files/afficheur_lcd_2x16_arduino.pdf
    • https://cdn.shopify.com/s/files/1/0437/5409/4743/files/22007457236.pdf
    • https://cdn.shopify.com/s/files/1/0435/9123/7791/files/viputaxivosepajaduki.pdf
    • https://cdn.shopify.com/s/files/1/0437/3915/2535/files/31529198505.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/8003629611.pdf
    • https://cdn.shopify.com/s/files/1/0432/1535/6067/files/technology_in_action_11th_edition_free.pdf
    • https://cdn.shopify.com/s/files/1/0436/9930/6648/files/4451340332.pdf
    • https://cdn.shopify.com/s/files/1/0431/1541/3661/files/fomominozi.pdf
    • https://cdn.shopify.com/s/files/1/0431/9779/2420/files/zovilesijedawusotov.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_off00006590.bin
f4e566acd7e95db55ce7b550dd4950b512dfe0b2583ba55729d549579a40ac8a
pdf-font-stream PDF embedded font (sfnt) at offset 0x6590 5548 bytes
font_01_sfnt_off00007881.bin
e99b3ae3fda04e6dfb9f64c04c67368d008ec9560b4664c56b03d7475980ddef
pdf-font-stream PDF embedded font (sfnt) at offset 0x7881 10132 bytes