Malicious PDF — malware analysis report

Static analysis result for SHA-256 90a5d6ba0fc53886…

MALICIOUS

PDF

67.7 KB Created: 2021-03-24 08:58:10 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: 8547f129084337df2ef4da9e104d3f27 SHA-1: 3d9f0428222f0993d74ce559715f2ecbd24406da SHA-256: 90a5d6ba0fc53886f1960ea848fb69092ba4f9f80418e02eda2aa27addede3b4
186 Risk Score

Malware Insights

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

The PDF file contains numerous external links, many hosted on disposable domains, suggesting a link farm or phishing campaign. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URLs point towards a tactic of directing users to potentially malicious sites under the guise of a utility.

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 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.
  • 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.
  • 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://vilenefex.ru/award?keyword=join+pdf+files+online+free PDF link annotation
    • http://telgrm.site/ponorogesasifutebijajisep1uwuu.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4411683/normal_5ffb761c62d87.pdfIn PDF document text
    • https://wulilunize.weebly.com/uploads/1/3/1/0/131071037/jajeteje.pdfIn PDF document text
    • https://nefalitarula.weebly.com/uploads/1/3/4/3/134308949/4445747.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4505102/normal_5ff805a41897c.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4370737/normal_5ffa50a568bfd.pdfIn PDF document text
    • http://trikolor.site/apex_launcher_apk_4._0._1g1kw6.pdfIn PDF document text
    • http://yandex-delivery.cc/48763915899604aw.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4491426/normal_5ff3b64343b7d.pdfIn PDF document text
    • https://mazerobuwi.weebly.com/uploads/1/3/1/3/131398334/1378993.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4454424/normal_5fdb904f46a2a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4411682/normal_60594b4ab7bee.pdfIn PDF document text
    • https://supavutoni.weebly.com/uploads/1/3/4/7/134713891/9640284.pdfIn PDF document text
    • https://pebogifi.weebly.com/uploads/1/3/1/4/131438694/noxurizafegezo.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/2530c67c-658c-472e-bd52-003fa94f90ff/how_to_get_into_pipefitters_union.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4d680a67-0647-4e34-97e5-cfb857cf6b90/46879139568.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/14873d65-88ac-4567-9ef9-b9230e729245/which_of_the_following_are_the_components_of_the_mission_command_system_ssd_4.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/65f5a38a-00d8-4ae0-aa89-09921ec4866d/does_taco_bell_have_low_carb_options.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/03a34195-7e77-47e1-a059-df6c36bb6cb1/rlc_circuit_lab_report_abstract.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/862b00d3-0e01-4944-8caf-cf62145bbc67/wise_wiser_wisest_meaning.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5947cdb8-4a85-4ba5-a808-5f5a9e3af737/2003_jeep_liberty_sport_engine_for_sale.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ba1f4606-210f-4094-bac6-8967ee9d335a/85781043134.pdfIn 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_off0000cb94.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB94 4816 bytes
SHA-256: f0bbd36c851b7383a71ea797728a9bafd6767f58782e318780aefd7c9c78eee8
font_01_sfnt_off0000dc06.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC06 10556 bytes
SHA-256: cfc2ce3601d20ade57c4d5edf116d40de1e5fd0442182d300b8a1acbe673437e