Malicious PDF — malware analysis report

Static analysis result for SHA-256 849ae4d3f76d278e…

MALICIOUS

PDF

34.7 KB Created: 2020-08-28 23:46:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 5839390923400bce003c25a3d8bff456 SHA-1: 330a8d4acd37c4cc90c12c90cbdb3c7ea1408e67 SHA-256: 849ae4d3f76d278ee364ebb31ec8b37e5a851fa9e56c9c2405162512b093d356
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a link that redirects to a malicious URL, identified by the PDF_MALICIOUS_REDIRECTOR_LINK heuristic. The document body and embedded links suggest a lure related to academic content, likely to trick users into visiting the malicious site. 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.ru/wix?keyword=cracking+the+sat+subject+test+in+physics+16th+edition+pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://static.usrfiles.com/ugd/b8c837_fd8539a7c5b848be8d4ab155ebe52973.pdf
    • https://static.usrfiles.com/ugd/b8c837_9b7fd98a56984821900bff5466b75b4a.pdf
    • https://static.usrfiles.com/ugd/b8c837_20de3a8b3a7c429c996668ffc80d8e8f.pdf
    • https://static.usrfiles.com/ugd/b8c837_f81cc0d72986438190d1c685ee02e642.pdf
    • https://cdn.shopify.com/s/files/1/0432/6345/9496/files/bhu_bsc_agriculture_syllabus_2018.pdf
    • https://cdn.shopify.com/s/files/1/0462/3033/9735/files/delete_browsing_history_in_google_chrome_android.pdf
    • https://cdn.shopify.com/s/files/1/0431/6404/1373/files/online_form_of_sainik_school_2018.pdf
    • https://cdn.shopify.com/s/files/1/0430/9568/7328/files/animal_farm_chapter_wise_summary.pdf
    • https://cdn.shopify.com/s/files/1/0433/1687/1326/files/fetidesatogemumopoxeneli.pdf
    • https://cdn.shopify.com/s/files/1/0430/6924/3549/files/39485939398.pdf
    • https://cdn.shopify.com/s/files/1/0430/2651/4077/files/7258887937.pdf
    • https://cdn.shopify.com/s/files/1/0434/5335/0053/files/2155_john_deere.pdf
    • https://cdn.shopify.com/s/files/1/0437/6661/2119/files/bungay_high_school_and_sixth_form_centre.pdf
    • https://cdn.shopify.com/s/files/1/0434/1379/9066/files/30034526151.pdf
    • https://cdn.shopify.com/s/files/1/0431/6119/0554/files/31427504413.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/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000486c.bin
61b25f0e82d4c74834a648309962949f48ce9e0f429e53af5061f5572b1084ec
pdf-font-stream PDF embedded font (sfnt) at offset 0x486C 5880 bytes
font_01_sfnt_off00005c71.bin
bf7274ed21afb4ccccfbf91fafbaeb38fa66c7edc5b3e22f596fa78706d08dcf
pdf-font-stream PDF embedded font (sfnt) at offset 0x5C71 9664 bytes