Malicious PDF — malware analysis report

Static analysis result for SHA-256 251cb8f21499d70f…

MALICIOUS

PDF

71.0 KB Created: 2021-04-06 22:18:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: 685e2e40d96b72753b14c8868a2afe8b SHA-1: 569a40f0eb3ee2a319cccba9c13fe1a4c508478b SHA-256: 251cb8f21499d70fd8dd116e46dd332ad3bcaa4310861d3e620069a924bff312
134 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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://xajibur.ru/123?utm_term=fanboys+coordinating+conjunctions+worksheet+pdf PDF link annotation
    • https://cdn.sqhk.co/tukawezezo/hjhjUjh/76381707391.pdfIn PDF document text
    • https://cdn.sqhk.co/kewawukufiju/gw3icgB/65189711536.pdfIn PDF document text
    • https://cdn.sqhk.co/kunimoxifagi/jhf85XC/dapawuxuxuwigixix.pdfIn PDF document text
    • https://cdn.sqhk.co/vimanagadu/BHhfWhh/21606865969.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4366408/normal_5ff19c6b6633e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4474450/normal_605abdf744325.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4423750/normal_604fc3d41287a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4389793/normal_604b469706aff.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4382189/normal_600d2540abeb1.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/bc1b2e30-e2e4-402d-a6df-4498b1c2228d/saeco_royal_coffee_machine_service_manual.pdfIn PDF document text
    • https://fb9345b8-40be-4608-a8ff-9c5427dba92f.filesusr.com/ugd/98d639_cc7264fb05b941e09eccd73725d40b1a.pdf?index=trueIn PDF document text
    • https://1350f94c-8d6f-42b4-8351-24983ad6a49a.filesusr.com/ugd/4aae87_b66ac5c7c4d04b9b91e61d3c5fe63717.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/65dd5440-425d-4684-83f2-0526d817414c/kegogazoburavusule.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0f287044-3ff3-49ca-8deb-f01f992f19f4/how_to_set_a_cateye_enduro_8.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/dd8f9e12-a87c-4deb-b913-dfb204ac1347/80404296298.pdfIn PDF document text
    • https://f421159b-d329-41e8-bc42-072bc93e4c50.filesusr.com/ugd/65d6f7_ddc1952426f64230995cc141e41e6e66.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/28c556af-6c04-4f06-aadb-82df1740a65d/what_was_the_governments_termination_policy_apex.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6bc0e953-e7a5-4244-b37d-c22cf9895024/les_miserables_2012_gavroche_song_lyrics.pdfIn PDF document text
    • https://02408c19-b9f6-4996-a596-1d5b7e46c8d3.filesusr.com/ugd/c83fdb_598e4d21a0c84f499924be65dbf4a74c.pdf?index=trueIn PDF document text
    • https://0ecef3a8-5193-4df1-8dcb-1b7dd0f2be2a.filesusr.com/ugd/e6092c_a66a762f6dba439992d0dc3b8dcd722f.pdf?index=trueIn PDF document text
    • https://da54c32a-99c7-4590-8520-800dd2d1cae3.filesusr.com/ugd/7973d2_23134415d71140e4a3188906008cafa7.pdf?index=trueIn PDF document text
    • https://66f9544f-8325-470d-a543-c07714603334.filesusr.com/ugd/4b2642_22a456f7f3104f328145e33db1137c86.pdf?index=trueIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d578.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD578 5816 bytes
SHA-256: c94ff0b9b43addf9c0bd2fd92b00607f401eee1ae8ab40a02b7bc8f578f4d80e
font_01_sfnt_off0000e95a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE95A 10292 bytes
SHA-256: 54f5e28bdff6d452725fdf0fa35f2be1ca7ce0a6317e3265b3fbb4908bb644f5