Malicious PDF — malware analysis report

Static analysis result for SHA-256 7a41c378f148b74a…

MALICIOUS

PDF

38.3 KB Created: 2020-08-20 07:26:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 75d9493b4a2e3bdb0034bdb7ab995ec4 SHA-1: 2d39905d283222c6019fbb80b2829a5feaaba7d9 SHA-256: 7a41c378f148b74a8868916b696bd0260a94a486f0ae1b4106e3bacc3eca3637
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded links, many of which point to external PDF files, suggesting a link farm or SEO poisoning attempt. One of the primary links, https://ttraff.ru/pify?keyword=cute+baby+laughing+ringtone+free, is flagged as a malicious redirector. The ML classifier also strongly indicated maliciousness. The document body, though heavily obfuscated, contains references to the malicious URL.

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=cute+baby+laughing+ringtone+free
    • http://files.alexlanshe.com/uploads/1/3/1/4/131438888/mikosojoxox.pdf
    • http://files.designsbybrunner.com/uploads/1/3/1/8/131856646/fozodusojad-tibima-punalax-wigiromadaxaxej.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0428/2066/5510/files/12392972245.pdf
    • https://cdn.shopify.com/s/files/1/0433/0812/2270/files/rubukoka.pdf
    • https://cdn.shopify.com/s/files/1/0435/3448/3616/files/davamilofuselise.pdf
    • https://cdn.shopify.com/s/files/1/0435/6558/0449/files/haakaa_manual_breast_pump_review.pdf
    • https://cdn.shopify.com/s/files/1/0430/3945/7431/files/pufolor.pdf
    • https://cdn.shopify.com/s/files/1/0440/1466/5886/files/paralytic_ileus_radiology.pdf
    • https://cdn.shopify.com/s/files/1/0429/3410/8323/files/3199644784.pdf
    • https://cdn.shopify.com/s/files/1/0430/1419/3311/files/53864466881.pdf
    • https://cdn.shopify.com/s/files/1/0434/6167/3126/files/wabijosusufodeg.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_off000058bd.bin
b49e1fa0e0b05635685cff0f9e7667ac1fc6aea4eaad89b3f2c276bdb8179292
pdf-font-stream PDF embedded font (sfnt) at offset 0x58BD 4996 bytes
font_01_sfnt_off000069be.bin
3d19279dc61068163d35e7058dd61325d0dd93f8b233d57cf026b3d88a7b84f4
pdf-font-stream PDF embedded font (sfnt) at offset 0x69BE 10240 bytes