Malicious PDF — malware analysis report

Static analysis result for SHA-256 81e6702f19fdad6f…

MALICIOUS

PDF

40.3 KB Created: 2020-08-07 09:55:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 6f3d720371aeaf86788f78aa18db5ed4 SHA-1: 5021422d1241da5c3e82583ca3fd5e8e6e8aa80e SHA-256: 81e6702f19fdad6f4431d904b740ed45f150f6673d647f05cef1f4edce551d7d
154 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many of which point to a redirector service (ttraff.ru) disguised as academic resources. The ML classifier strongly indicates maliciousness, and the PDF_SEO_LINK_FARM heuristic confirms the presence of a link farm designed to direct users to potentially harmful content. No scripts were extracted, but the embedded links are the primary attack vector.

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=multilingual+education+thesis+pdf
    • http://files.bhamcommunityacupuncture.com/uploads/1/3/0/7/130776327/cc67b95f7f.pdf
    • http://files.bhurbanhillapartments.com/uploads/1/3/2/7/132740978/2785935.pdf
    • http://files.questswim.com/uploads/1/3/1/4/131453251/pabazekonoze_gonuzop_zuwenobawariv.pdf
    • http://rofugasep.joshuablubuhs.com/uploads/1/3/1/6/131636725/gozumusanotak.pdf
    • http://files.redbearoriginals.com/uploads/1/3/0/7/130776393/5e9deee90.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0432/5395/6758/files/kojarexo.pdf
    • https://cdn.shopify.com/s/files/1/0431/5031/1579/files/17726121972.pdf
    • https://cdn.shopify.com/s/files/1/0428/0100/4707/files/sogamikibijoduvewasikeb.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/sejil.pdf
    • https://cdn.shopify.com/s/files/1/0430/0469/0581/files/48163177752.pdf
    • https://cdn.shopify.com/s/files/1/0428/6667/1782/files/larson_calculus_9e.pdf
    • https://cdn.shopify.com/s/files/1/0430/7589/5447/files/sibatelowixo.pdf
    • https://cdn.shopify.com/s/files/1/0433/0346/9221/files/movokawapigon.pdf
    • https://cdn.shopify.com/s/files/1/0429/0448/6055/files/manual_of_parliamentary_procedure.pdf
    • https://cdn.shopify.com/s/files/1/0434/0783/5303/files/60019689558.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_off00006023.bin
071e0afc0b264a57dde2123a1d2e20b97660bd617ba1155a6e193d2b824f37de
pdf-font-stream PDF embedded font (sfnt) at offset 0x6023 5324 bytes
font_01_sfnt_off00007250.bin
58ffc6a8908fbb0dcd134d4a34b426d16003fc11c43777ed508c9ba189816728
pdf-font-stream PDF embedded font (sfnt) at offset 0x7250 10088 bytes