Malicious PDF — malware analysis report

Static analysis result for SHA-256 56b71f279db85b1e…

MALICIOUS

PDF

38.3 KB Created: 2020-08-23 01:29:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d847bca4630218d8d6247de0e16c136a SHA-1: e785b6f884f2da0a720312e23b06a2cae626dcf6 SHA-256: 56b71f279db85b1e104c477de2af6008e5880e456b665cb9b85846c0632dc762
152 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, with one specifically pointing to a known malicious redirector. The ML classifier also strongly indicated maliciousness. The document body appears to be a mix of garbled text and URLs, suggesting it was generated programmatically to host these links. The primary attack pattern involves leveraging these links, likely for SEO poisoning or to redirect users to malicious content.

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=dewalt+7740+radial+arm+saw+manual
    • http://files.audreymarychapuis.com/uploads/1/3/0/7/130776828/8987641.pdf
    • http://files.inglesespecializado.com/uploads/1/3/1/3/131383434/soxetanefa.pdf
    • https://cdn.shopify.com/s/files/1/0432/9000/1572/files/moluvipunekajaxejizuwepa.pdf
    • https://cdn.shopify.com/s/files/1/0433/8365/2506/files/mofiminolazewozev.pdf
    • https://cdn.shopify.com/s/files/1/0466/3099/4085/files/48025880024.pdf
    • https://cdn.shopify.com/s/files/1/0429/7634/6266/files/osceola_county_daily_arrest.pdf
    • https://cdn.shopify.com/s/files/1/0433/7372/3800/files/jejunagofuxotapapitesape.pdf
    • https://cdn.shopify.com/s/files/1/0435/2576/7327/files/balutupefenisorizose.pdf
    • https://cdn.shopify.com/s/files/1/0439/7416/4638/files/30576412624.pdf
    • https://cdn.shopify.com/s/files/1/0430/6314/8706/files/nerefe.pdf
    • https://cdn.shopify.com/s/files/1/0431/8029/4298/files/62892026162.pdf
    • https://cdn.shopify.com/s/files/1/0429/2309/8279/files/86267710089.pdf
    • https://cdn.shopify.com/s/files/1/0429/6704/0154/files/62084254883.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_off000056d4.bin
4650d8d42e1ac482e755e1d5b0311466d08b00229f0d928fc1e3c26079eb2c90
pdf-font-stream PDF embedded font (sfnt) at offset 0x56D4 5372 bytes
font_01_sfnt_off0000691f.bin
4ecc1db6a331145bcc0e8f999b9fb330734c1b6f5b6dd9ad82e9a2caae2ae21f
pdf-font-stream PDF embedded font (sfnt) at offset 0x691F 10364 bytes