Malicious PDF — malware analysis report

Static analysis result for SHA-256 87089fdefd37b4b9…

MALICIOUS

PDF

84.1 KB Created: 2021-04-23 21:52:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-10
MD5: fb568b1be6d3df251e21d2aec7e3f8d0 SHA-1: cb557d326886a7a5e9389d890ae66c822f3a5538 SHA-256: 87089fdefd37b4b96c8394235100e418756aa7b2352cbb3a72f7374d6ff22a2c
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. It contains numerous embedded URLs, with at least two pointing to suspicious domains ('zajinet.ru' and 'idealslim-italiaofficial.site'). The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically identifies the PDF as a link farm on disposable hosting, suggesting a phishing or redirection scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

Heuristics 5

  • 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 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://zajinet.ru/strik?utm_term=sanyo+40+inch+led+tv+reviews PDF link annotation
    • http://idealslim-italiaofficial.site/fozawadoxeb8s6j9.pdfIn PDF document text
    • https://cdn.sqhk.co/luwiwaduna/xE5hbKw/download_game_dragon_village_cheat.pdfIn PDF document text
    • https://cdn.sqhk.co/dadakafopina/MPcqjaU/7878611151.pdfIn PDF document text
    • https://cdn.sqhk.co/kajurineg/dhckpgh/26448549064.pdfIn PDF document text
    • https://cdn.sqhk.co/suxumeva/giOY5QK/sefijafepeg.pdfIn PDF document text
    • http://apsdd54gfv.xyz/ps_store_cyber_monday_2019wpb9j.pdfIn PDF document text
    • http://supsun-aero.com/63817684640uw0x4.pdfIn PDF document text
    • https://cdn.sqhk.co/vekuzajomugi/j3icoFB/super_sour_bubble_gum_pops_calories.pdfIn PDF document text
    • http://vas-rem.ru/59573421638axio6.pdfIn PDF document text
    • http://igme.site/gikunukififipazedoro2n2.pdfIn PDF document text
    • http://tatabumilik.iblogger.org/tipozulefili.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/351275b2-30e7-4d0b-a3a5-99f5ef34b6e9/buffalo_multi_function_rice_cooker_review.pdfIn PDF document text
    • http://digotadegijo.epizy.com/decimal_multiplication_worksheet_with_answers.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/97ba560d-71bd-4d4a-9cd3-bde375ccb533/25191991722.pdfIn PDF document text
    • http://beperedusewigu.epizy.com/galabewipapafefepi.pdfIn PDF document text
    • https://s3.amazonaws.com/luropi/6289013185.pdfIn PDF document text
    • http://robabunegulawi.rf.gd/diabetes_canada_guidelines_diagnosis.pdfIn PDF document text
    • http://tuketusave.rf.gd/atherosclerosis_2020.pdfIn PDF document text
    • https://s3.amazonaws.com/redegelesibif/nolajuvuruwiturodobomup.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c460816b-8157-4ac5-81f7-fd6789dcf78a/96115959411.pdfIn PDF document text
    • https://s3.amazonaws.com/dukexajuj/39233060717.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e76db8bd-0203-405f-85c2-0d14ca9ca69b/bogemoxoromaw.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e53dcaa8-ccd1-4351-a4ce-7e7a40834098/52830652614.pdfIn PDF document text
    • https://s3.amazonaws.com/fujadabez/nsw_mines_department_reportable_incidents.pdfIn PDF document text
    • https://s3.amazonaws.com/jejulurowev/62636746302.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/97af4888-430d-4921-8ed6-44ae208da7eb/83774212739.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0c4cdd9b-7994-4aed-b478-4de04373dfbd/butejukefazifos.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f402.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF402 5616 bytes
SHA-256: 90aafe83d8da00e1b1d7629d996209dd911908b38bddd1c0d64c95f85f6cc895
font_01_sfnt_off00010738.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10738 11084 bytes
SHA-256: ecdd3d1ce61f96da340e9c8300e1ef0648e5249c68fd12e3b51588a4f683b6cb
font_02_sfnt_off00012d27.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D27 16164 bytes
SHA-256: ead7fd593d7f5feef6f283420e9b55f8fa4552f107c64b0063d474dd3355abd8