Malicious PDF — malware analysis report

Static analysis result for SHA-256 b335aadbac4b2216…

MALICIOUS

PDF

49.0 KB Created: 2020-08-18 13:22:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 2994fe6fb7fc61547c4053208eac83f0 SHA-1: 6a15c8da5addb2fa429a372426142c39d7e6206a SHA-256: b335aadbac4b22168d2e9f073cef18a53182e4be89542d92d4bef5498ca993ac
154 Risk Score

Malware Insights

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

The PDF contains a link farm designed to redirect users to malicious infrastructure, specifically identified by the heuristic PDF_MALICIOUS_REDIRECTOR_LINK. The document body, though heavily obfuscated, contains the URL https://ttraff.com/pify?keyword=high+school+drawing+book+pdf, suggesting a lure to a malicious site disguised as a drawing book. The ML classifier also strongly indicated maliciousness.

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.com/pify?keyword=high+school+drawing+book+pdf
    • http://files.sp-arms.com/uploads/1/3/1/1/131164236/dufuzewajajavokak.pdf
    • http://files.scribeathisfeet.com/uploads/1/3/0/7/130739951/zizupilusifax-bazogike-xifugizib.pdf
    • https://cdn.shopify.com/s/files/1/0434/0423/0805/files/71308685949.pdf
    • https://cdn.shopify.com/s/files/1/0438/4971/1781/files/62710052200.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/19490865332.pdf
    • https://cdn.shopify.com/s/files/1/0432/5949/4555/files/mevusurivi.pdf
    • https://cdn.shopify.com/s/files/1/0431/5653/7505/files/muscle_gain_workout_plan_for_beginners.pdf
    • https://cdn.shopify.com/s/files/1/0431/2956/9429/files/jubufabeguwavujogule.pdf
    • https://cdn.shopify.com/s/files/1/0431/1410/2951/files/hudson_park_pima_cotton_sheets.pdf
    • https://cdn.shopify.com/s/files/1/0431/0417/4233/files/paradise_lost_milton.pdf
    • https://cdn.shopify.com/s/files/1/0429/6045/3785/files/6449838571.pdf
    • https://cdn.shopify.com/s/files/1/0429/1792/0934/files/3d_model_cars.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_off000081cc.bin
045c7d1df974d697ed417f5b27c017b06fb8cb9d079fa5d2af1b7e68f1aa58c1
pdf-font-stream PDF embedded font (sfnt) at offset 0x81CC 5672 bytes
font_01_sfnt_off0000951a.bin
ba81422ef750d6755262467ccf0c9fa68c76073ca689c4558ecffd4c6f284458
pdf-font-stream PDF embedded font (sfnt) at offset 0x951A 10120 bytes