Malicious PDF — malware analysis report

Static analysis result for SHA-256 f90b915a3c57a0bb…

MALICIOUS

PDF

45.3 KB Created: 2020-07-30 10:11:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 34b72ad063368fe8a41139813d5acdef SHA-1: 13ca43975e6e3ddf77018f18650e66a79adf79bd SHA-256: f90b915a3c57a0bbe5b0f21237a0f61963f979e30906466cf2f605e6ee08cd7c
152 Risk Score

Malware Insights

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

The PDF was flagged by multiple critical heuristics for containing a malicious redirector link and a large external PDF link farm. The ML classifier also strongly indicated maliciousness. The document body, though heavily obfuscated, contains text related to 'acls emergency drugs pdf' and mentions 'wkhtmltopdf', suggesting a lure document. The primary attack pattern involves redirecting users to potentially harmful content via the numerous embedded links.

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=acls+emergency+drugs+pdf
    • http://files.americanfoursquare.us/uploads/1/3/2/7/132740218/majibomavapakabopi.pdf
    • http://files.donnasdailydish.com/uploads/1/3/2/6/132681985/9442295.pdf
    • http://files.statesocietyofflorida.org/uploads/1/3/1/6/131637419/bonudosaguniwal.pdf
    • http://files.joshuajayindo.com/uploads/1/3/1/4/131437980/rojaxarumonanonon.pdf
    • http://files.joshuajayindo.com/uploads/1/3/1/4/131437980/
    • https://cdn.shopify.com/s/files/1/0432/5575/9011/files/mefomagixupilunu.pdf
    • https://cdn.shopify.com/s/files/1/0432/1335/7211/files/sadubojunupekaxitamepan.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/56070096689.pdf
    • https://cdn.shopify.com/s/files/1/0430/8199/0295/files/rowerebetenuzalebowo.pdf
    • https://cdn.shopify.com/s/files/1/0431/6404/1373/files/givifazerezukavapagagirid.pdf
    • https://cdn.shopify.com/s/files/1/0433/6576/1176/files/11755769401.pdf
    • https://cdn.shopify.com/s/files/1/0432/0113/4747/files/salufinovilodevej.pdf
    • https://cdn.shopify.com/s/files/1/0429/5992/9503/files/87372193222.pdf
    • https://cdn.shopify.com/s/files/1/0440/9065/4870/files/guredarurigomanewow.pdf
    • https://cdn.shopify.com/s/files/1/0430/1111/3123/files/43832179707.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_off00007407.bin
862666deb869bffaf77586c6fbe28c252f79e3fb888ce6bba6d5b95778e14170
pdf-font-stream PDF embedded font (sfnt) at offset 0x7407 5000 bytes
font_01_sfnt_off000084ea.bin
39b0e2e97697189f68ff640e735c18de0fc71de53b7ce7ea9f1c1550450d1547
pdf-font-stream PDF embedded font (sfnt) at offset 0x84EA 10376 bytes