Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9321c8658431732…

MALICIOUS

PDF

72.8 KB Created: 2021-04-06 21:43:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 87cfd233f3bcf89db8b4c3b2cce7bdbb SHA-1: 5acd350a2c2d89e962bd146798171f7f9045e8d5 SHA-256: a9321c8658431732f3919da829066f9915978514f520cb9db4acdab65b6c2495
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a large number of external links, as indicated by the PDF_SEO_LINK_FARM and PDF_SEO_DISPOSABLE_LINK_FARM heuristics. The ML classifier and ClamAV also flagged this PDF as malicious, with ClamAV identifying it as Pdf.Phishing.Trojan. The primary attack pattern appears to be directing users to potentially malicious websites through a link farm, which is a common tactic for phishing or distributing further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://baarspo.ru/award?keyword=bootstrap+4+cheat+sheet+pdf+download PDF link annotation
    • http://womizepivilora.sportsontheweb.net/60875275628.pdfIn PDF document text
    • https://vazanekufom.weebly.com/uploads/1/3/5/3/135322674/tukoj-vuvokitiw-bamapixub-nufoki.pdfIn PDF document text
    • http://just-gopro.com/fishing_planet_texas_guide_ps41sh7e.pdfIn PDF document text
    • https://zakebixed.weebly.com/uploads/1/3/5/3/135387858/felexasera.pdfIn PDF document text
    • http://dirtygirl.fun/88545914596nb1mo.pdfIn PDF document text
    • http://ig-copyrightnoticehelp.com/pefaravud9g8t6.pdfIn PDF document text
    • http://vubitim.sportsontheweb.net/business_plan_template_fill_in_the_blanks.pdfIn PDF document text
    • https://xudezilo.weebly.com/uploads/1/3/0/7/130739240/7410741.pdfIn PDF document text
    • http://wwwbcpzonasegura-viabcp.com/how_to_be_smart_like_sora_and_shiropqx3y.pdfIn PDF document text
    • http://gifagudilul.mypressonline.com/70427889798.pdfIn PDF document text
    • http://fibisazorowax.mypressonline.com/fuzinekoj.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://b304dada-1952-41b2-af44-d16a3232bb3f.filesusr.com/ugd/c19c34_0dd967c4d2de45309e1bd150ea2e42a6.pdf?index=trueIn PDF document text
    • https://0a497e50-07dd-462d-832d-d8678f741a8e.filesusr.com/ugd/5f857b_4d6362b6b00046759e42d2eeba8b828c.pdf?index=trueIn PDF document text
    • https://b962c29b-1a16-4d97-a630-68bfda4e66eb.filesusr.com/ugd/3e0cb9_eaf62b4902004856aa53785eda2b663b.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/096cefc1-838f-4dd1-89a8-f4ad50e755ca/why_is_apc_backup_battery_beeping.pdfIn PDF document text
    • https://caf0f927-206f-4b4e-aa34-0dd3da53679b.filesusr.com/ugd/83d902_f1c300827eaa4fa5a51d2b57e90c2c35.pdf?index=trueIn PDF document text
    • https://f110cc6a-49d6-427c-9ab6-a3a4d323b004.filesusr.com/ugd/9e53d4_7c5e47bb67ce4436ad78267ffb7e553e.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/4f54cbc2-a264-4148-b1c2-621e6c8e4d9a/97207002422.pdfIn PDF document text
    • https://c2093f15-f4fb-4bda-9582-db5404103fa6.filesusr.com/ugd/b28561_67dcaf5b871142ffb4100ad03721837b.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/37734e34-3942-455f-a864-54e44fce1ca7/understanding_mass_haul_diagrams.pdfIn PDF document text
    • https://229c3593-bb94-4e5d-9b9f-ca3747df48ef.filesusr.com/ugd/145364_0e47e478fcf0455ea11bc5fe11f02dfc.pdf?index=trueIn PDF document text
    • https://71f68c9c-1037-483c-a0ca-f268b7ddd3c8.filesusr.com/ugd/87fdc7_eae6d11fdbbd4912b14da79190b51c25.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_off0000de9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE9B 5472 bytes
SHA-256: 7c0682ca2ccd140c750ee0fd8df36a7bd2e2603f36cf106706f0cd1cb9eeaa65
font_01_sfnt_off0000f14f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF14F 10756 bytes
SHA-256: 8601efb2dc99ae9160658318956b0cae2125f538e47748b13229303e3fea25a6