Malicious PDF — malware analysis report

Static analysis result for SHA-256 33a421afa60ea892…

MALICIOUS

PDF

44.2 KB Created: 2020-08-08 08:54:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d736bc18b837a54b302a586d597b7aa2 SHA-1: ea6709a8b332a5c5cf93050b403ef084f8e2fd8e SHA-256: 33a421afa60ea892bd04f09584edd08562ee69c49339b10a229910207b20c500
152 Risk Score

Malware Insights

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

The PDF contains embedded links that are part of a link farm, with one critical link pointing to a known malicious redirector. The document body, though heavily obfuscated, contains text related to interview questions and the malicious URL, suggesting a social engineering lure. 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=interview+questions+and+answers+tell+me+about+yourself+pdf
    • http://files.swimscaape.com/uploads/1/3/2/7/132712050/280937.pdf
    • http://files.navakarnatakanirmana.com/uploads/1/3/1/4/131453365/komenarelimuz.pdf
    • http://files.playmusiccompany.com/uploads/1/3/1/0/131070938/sowazolenogeg_volenuxupowor_fanibukolineja.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/demesudixagivok.pdf
    • https://cdn.shopify.com/s/files/1/0440/1460/0342/files/maths_worksheets_grade_4.pdf
    • https://cdn.shopify.com/s/files/1/0430/5492/3925/files/64671455192.pdf
    • https://cdn.shopify.com/s/files/1/0428/1057/2966/files/20415750746.pdf
    • https://cdn.shopify.com/s/files/1/0441/1781/9544/files/fios_channel_lineup_2015.pdf
    • https://cdn.shopify.com/s/files/1/0430/0174/1463/files/44166837413.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/pafinekumukomotutawewokab.pdf
    • https://cdn.shopify.com/s/files/1/0428/5041/8847/files/98911647662.pdf
    • https://cdn.shopify.com/s/files/1/0435/2763/5096/files/arboles_de_decision_en_r.pdf
    • https://cdn.shopify.com/s/files/1/0433/1280/8091/files/74115518116.pdf
    • https://cdn.shopify.com/s/files/1/0432/2318/7616/files/college_budget_worksheet.pdf
    • https://cdn.shopify.com/s/files/1/0429/9957/8773/files/73920807720.pdf
    • https://cdn.shopify.com/s/files/1/0435/5234/2184/files/70407250791.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_off00006cea.bin
d5ec3700a6e22e00f14ae78d8ae2850f6026be4cd147d171ad2cdac2f89f991c
pdf-font-stream PDF embedded font (sfnt) at offset 0x6CEA 5644 bytes
font_01_sfnt_off00008018.bin
d99aa8df6a6f5de87f2525916e8b88f143d69ce87e53dea0c1d17338674a0ba3
pdf-font-stream PDF embedded font (sfnt) at offset 0x8018 10316 bytes