Malicious PDF — malware analysis report

Static analysis result for SHA-256 8fb1234439bda7a8…

MALICIOUS

PDF

35.5 KB Created: 2020-08-23 01:48:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 3814c0dc09f381548bfab6583296b409 SHA-1: c446cb10f2ebb256487dde87c26a69eb3a51a689 SHA-256: 8fb1234439bda7a8f11c45f1e8915f571ffb2e3c0f58c8303ef126b7b5908f97
152 Risk Score

Malware Insights

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

The PDF contains a significant number of embedded links, many of which point to external PDF files hosted on various domains. One URL, 'https://ttraff.ru/pify?keyword=shark+canister+vacuum+manual', is flagged as a known malicious redirector. The ML classifier strongly indicated maliciousness, and the presence of a link farm suggests an attempt to manipulate search engine results or distribute further 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.ru/pify?keyword=shark+canister+vacuum+manual
    • http://mubiwufu.littleromeinc.com/uploads/1/3/1/4/131453022/tezanujirejabelu.pdf
    • http://jemeze.jshempsters.com/uploads/1/3/2/6/132696414/1175670.pdf
    • https://cdn.shopify.com/s/files/1/0438/2654/4802/files/famonetubebinu.pdf
    • https://cdn.shopify.com/s/files/1/0434/6871/8233/files/co_op_housing_society_bye_laws_in_marathi.pdf
    • https://cdn.shopify.com/s/files/1/0434/2638/1975/files/answering_machine_for_landline_phones.pdf
    • https://cdn.shopify.com/s/files/1/0432/8616/7702/files/36700669968.pdf
    • https://cdn.shopify.com/s/files/1/0432/5654/5433/files/66755939063.pdf
    • https://cdn.shopify.com/s/files/1/0432/5238/3902/files/73944337697.pdf
    • https://cdn.shopify.com/s/files/1/0461/8865/8851/files/2_digit_addition_regrouping_word_problems_worksheet.pdf
    • https://cdn.shopify.com/s/files/1/0434/6835/7796/files/agricola_rules_revised.pdf
    • https://cdn.shopify.com/s/files/1/0428/2118/9788/files/48461645524.pdf
    • https://cdn.shopify.com/s/files/1/0430/3080/6679/files/60722404544.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/27360052690.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_off00004db6.bin
358faf8ab0fab0740c6aa3b76ad0eadb165c45b0d3a872c9ec4d5e8150015b39
pdf-font-stream PDF embedded font (sfnt) at offset 0x4DB6 5264 bytes
font_01_sfnt_off00005f6f.bin
22e0a4ba6fee8f701254b1a4e2f88b7496d2063abd0d2786a19eac22d92a9475
pdf-font-stream PDF embedded font (sfnt) at offset 0x5F6F 9868 bytes