Malicious PDF — malware analysis report

Static analysis result for SHA-256 22bafc31cda4cd2e…

MALICIOUS

PDF

44.5 KB Created: 2020-08-19 21:59:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: cd4360b00829670b8971a72878aac0d9 SHA-1: 397fbc10c719e1ef99fd12900e1f0152675ba924 SHA-256: 22bafc31cda4cd2ebc4452f8e7a0b9d8298c98c8939ca758128aba6b0bebdf1a
152 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many of which point to a link farm hosted on Shopify. One of these links, https://ttraff.ru/pify?keyword=printable+addition+worksheets+for+year+1, is identified as a malicious redirector. The document body, though heavily obfuscated, also contains this URL, suggesting the primary purpose is to redirect the user to malicious infrastructure. The ML classifier strongly supports the malicious nature of this PDF.

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.ru/pify?keyword=printable+addition+worksheets+for+year+1
    • http://rovel.startingupatstartups.com/uploads/1/3/0/8/130874332/3803807.pdf
    • http://foner.thepostamerican.com/uploads/1/3/1/6/131606289/durupesojolo.pdf
    • http://kudazagu.texaspoultryshrinkbags.com/uploads/1/3/2/8/132815732/sepitabadaja.pdf
    • http://pevis.wordbranchmedia.com/uploads/1/3/1/6/131606624/bokumejanerivujelog.pdf
    • https://cdn.shopify.com/s/files/1/0437/5340/6618/files/99281725147.pdf
    • https://cdn.shopify.com/s/files/1/0429/5108/2143/files/52442696711.pdf
    • https://cdn.shopify.com/s/files/1/0429/8348/9687/files/1465339423.pdf
    • https://cdn.shopify.com/s/files/1/0433/8548/7525/files/xobevomupagedibelalinili.pdf
    • https://cdn.shopify.com/s/files/1/0429/2562/1404/files/don_t_you_evah.pdf
    • https://cdn.shopify.com/s/files/1/0430/8575/8628/files/a4988_datasheet_380k.pdf
    • https://cdn.shopify.com/s/files/1/0436/0863/7602/files/mcmurry_organic_chemistry_7th_edition.pdf
    • https://cdn.shopify.com/s/files/1/0439/6145/0654/files/cash_flow_ratio_analysis.pdf
    • https://cdn.shopify.com/s/files/1/0428/6939/1527/files/angry_bird_transformers_mod_apk_data.pdf
    • https://cdn.shopify.com/s/files/1/0429/6962/8828/files/generac_5500xl_parts.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_off000069b5.bin
bd4f21664b43047ecdb5dde21808a8cc74452ad31a979353008a4a9cb9218fcb
pdf-font-stream PDF embedded font (sfnt) at offset 0x69B5 5448 bytes
font_01_sfnt_off00007c41.bin
9138af2a900aca5ec6d5e18643dd0c1c982ab8905f548a812273cdddd3da213d
pdf-font-stream PDF embedded font (sfnt) at offset 0x7C41 12096 bytes