Malicious PDF — malware analysis report

Static analysis result for SHA-256 a00cf41f98eca67a…

MALICIOUS

PDF

68.4 KB Created: 2021-03-31 13:20:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: ac4cedd2d7aa5bf2874a7d4f467022c9 SHA-1: 77396cff03c52fcafbc8eebc8b4230cb21c5965e SHA-256: a00cf41f98eca67ac8ee00b17c3e9ab9b5b2132a6271b9f9c9b1b7ff00d232e7
156 Risk Score

Malware Insights

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

The PDF file contains numerous external links, many pointing to Weebly-hosted PDFs with suspicious naming conventions, indicative of a link farm or SEO manipulation tactic. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and extensive external linking suggest it's designed to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 5

  • 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.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://nipisod.ru/strik?utm_term=how+to+replace+belt+on+kenmore+70+series+washer
    • https://nosadipopone.weebly.com/uploads/1/3/4/4/134470180/kepusotezijux_ropopifidix_xemuvizu.pdf
    • https://zuberexuwaxif.weebly.com/uploads/1/3/4/5/134501439/fukuxu-bubasedoxopukob-medegivifofegug.pdf
    • https://guxofavopadowan.weebly.com/uploads/1/3/5/9/135988616/romuvi.pdf
    • https://rotugufe.weebly.com/uploads/1/3/5/3/135315725/zadusotesenewap.pdf
    • https://cdn-cms.f-static.net/uploads/4411696/normal_5fd97ad4075cf.pdf
    • https://lerexujirizafet.weebly.com/uploads/1/3/4/3/134344290/rojedibod.pdf
    • https://cdn-cms.f-static.net/uploads/4494140/normal_604e370f37018.pdf
    • https://static.s123-cdn-static.com/uploads/4495696/normal_5fcb1e42983de.pdf
    • https://wewuketis.weebly.com/uploads/1/3/5/3/135327502/ac51128fc90.pdf
    • https://cdn-cms.f-static.net/uploads/4417645/normal_6017a3d10ad50.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/gavexilatuvitaz/mukadon.pdf
    • https://s3.amazonaws.com/fukepez/health_and_safety_council_global_health.pdf
    • https://s3.amazonaws.com/tosego/design_an_anglo_saxon_village_worksheet.pdf
    • https://s3.amazonaws.com/juzowilipi/8547112331.pdf
    • https://uploads.strikinglycdn.com/files/76132bf9-8864-4ce4-a28e-aecd9453e827/sennheiser_hdr_120_ii_wireless_headphones.pdf
    • https://s3.amazonaws.com/tajimipojimo/shows_a_gas_contained_in_a_vertical_piston-cylinder_assembly.pdf
    • https://s3.amazonaws.com/posufij/66575453461.pdf
    • https://uploads.strikinglycdn.com/files/5fb4df27-e0e5-4b72-bf4b-53db2ca3b4f3/8259772898.pdf
    • https://s3.amazonaws.com/viregujipowuru/flight_simulator_game_3d.pdf
    • https://s3.amazonaws.com/musoxifuvitalo/casuarina_glauca_prostrate_form.pdf
    • https://uploads.strikinglycdn.com/files/d3d0c5b3-7df4-4e0e-85b4-9eedeeb5ce3a/razujidib.pdf
    • https://uploads.strikinglycdn.com/files/ddd894bd-2473-48ae-ae51-dd5316348b8a/pabugebaruzufoji.pdf
    • https://s3.amazonaws.com/jasipefulaxiduj/read_pendragon_book_1_online_free.pdf
    • https://s3.amazonaws.com/jagux/28837669998.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_off0000cdfb.bin
9b41cf882415ab5199720bbfb77ceb679cc16556d0f8f4b6d1dbb551e8340c0e
pdf-font-stream PDF embedded font (sfnt) at offset 0xCDFB 5652 bytes
font_01_sfnt_off0000e119.bin
caf6103b9fd0bedffceb8ddfdf39eb2d6c8b5e93d99b12555b5029b68a068e59
pdf-font-stream PDF embedded font (sfnt) at offset 0xE119 10176 bytes