Malicious PDF — malware analysis report

Static analysis result for SHA-256 98e8d5810061f0d7…

MALICIOUS

PDF

40.1 KB Created: 2020-08-16 19:29:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: dc9b24343dc9d807c224ca77745ace7f SHA-1: c476b142ab3f7ad96bf0af4defd1739bb4b07b66 SHA-256: 98e8d5810061f0d7d14c489c1c8721d07af4696824af3bf97796716dc41c0958
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 to other PDF files, constituting a link farm. One of these links points to a known malicious redirector, indicating a potential phishing or malware distribution attempt. The ML classifier strongly flagged this PDF as malicious. No scripts were extracted, and the document body was largely unreadable, but the presence of the redirector and link farm is sufficient evidence.

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=health+promotion+board+healthy+eating+guidelines
    • http://mupelage.stjosephtheworkersutton.co.uk/uploads/1/3/2/7/132740373/dotowovu.pdf
    • http://files.powerstrokeequipment.com/uploads/1/3/1/4/131406274/5b85c0.pdf
    • https://cdn.shopify.com/s/files/1/0431/9644/8917/files/gulajomumesugirituvujewi.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/48466687054.pdf
    • https://cdn.shopify.com/s/files/1/0437/8882/8829/files/gameboy_startup_sound.pdf
    • https://cdn.shopify.com/s/files/1/0430/1769/9477/files/37164061430.pdf
    • https://cdn.shopify.com/s/files/1/0437/1031/6694/files/libro_de_cantos_liturgicos.pdf
    • https://cdn.shopify.com/s/files/1/0434/9689/8724/files/19488572912.pdf
    • https://cdn.shopify.com/s/files/1/0435/2973/2248/files/ias_interview_questions_and_answers_free_download_in_english.pdf
    • https://cdn.shopify.com/s/files/1/0438/5135/0166/files/93823750858.pdf
    • https://cdn.shopify.com/s/files/1/0434/0056/0803/files/63566374212.pdf
    • https://cdn.shopify.com/s/files/1/0437/7182/2229/files/defakega.pdf
    • https://cdn.shopify.com/s/files/1/0427/7354/5116/files/jemiwutimokiguwebivovut.pdf
    • https://cdn.shopify.com/s/files/1/0450/1697/3476/files/tabla_de_alimentos_con_vitamina_d.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_off00005e57.bin
928c824817534b4200bb7f6257e49365ecf61f553d5a28e7d4e4844ad4e22d14
pdf-font-stream PDF embedded font (sfnt) at offset 0x5E57 5576 bytes
font_01_sfnt_off00007117.bin
5daf5d6e1bf00a0ecd62514535d34ea904e9030c8341b436818106f3e7839146
pdf-font-stream PDF embedded font (sfnt) at offset 0x7117 10024 bytes