Malicious PDF — malware analysis report

Static analysis result for SHA-256 21d97983a3856c9d…

MALICIOUS

PDF

77.1 KB Created: 2021-03-05 00:05:36 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 9e825648e9cf14d0c121d9ea79238f97 SHA-1: ce140d4ddc612a923e6059051b65d7872e9d7d00 SHA-256: 21d97983a3856c9df9536dac78022594078188c896c5d5178a3bba9fa1728158
186 Risk Score

Malware Insights

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

This PDF document contains a large number of external links, many hosted on disposable domains, suggesting a link farm or phishing attempt. The ClamAV detection and ML classifier strongly indicate maliciousness. The document body, though partially corrupted, suggests a lure related to assembling exercise equipment, which is likely a pretext to drive traffic to the malicious URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://baarspo.ru/strik?utm_term=how+to+assemble+a+schwinn+ic4 PDF link annotation
    • https://cdn.sqhk.co/kovezozeseg/Y2xhdmR/my_teaching_strategies_gold_login.pdfIn PDF document text
    • https://powelogub.weebly.com/uploads/1/3/1/8/131871449/3626544.pdfIn PDF document text
    • https://wafanipo.weebly.com/uploads/1/3/2/6/132695839/3339912.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4448550/normal_6019bdd81f6fc.pdfIn PDF document text
    • https://cdn.sqhk.co/winogolelog/jijChgW/xm_radio_hits_1_top_40_list.pdfIn PDF document text
    • https://vipukawolatu.weebly.com/uploads/1/3/4/4/134486161/tovererekop_dikisibu_pefazi.pdfIn PDF document text
    • http://selozufuwadapuw.66ghz.com/tujedugiludulazatopuvid.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4388063/normal_6035f535af68a.pdfIn PDF document text
    • https://cdn.sqhk.co/bepeguvovori/JjbX1sS/wepujo.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4378607/normal_5fde730953838.pdfIn PDF document text
    • http://rugozuravonabib.22web.org/bar_louie_menu.pdfIn PDF document text
    • https://sabidodavo.weebly.com/uploads/1/3/1/4/131408103/vanaxom_jozisuwokokina_goretomikumawob_sagedijodobukir.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4481275/normal_602077ab79052.pdfIn PDF document text
    • http://boburokopuxixud.iblogger.org/72678138186.pdfIn PDF document text
    • https://pitazifuriza.weebly.com/uploads/1/3/0/9/130969431/2158735.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://684917c6-b594-4497-9ea4-141105166a5b.filesusr.com/ugd/0dc9f5_9cb6b1926931446c8170ccb6fd6048a7.pdf?index=trueIn PDF document text
    • http://fumebuz.rf.gd/matlab_toolbox_download_free.pdfIn PDF document text
    • https://8641c524-1fb5-4292-87ed-dd72f64d6c22.filesusr.com/ugd/9b7d8a_d4c401e447064d8f85169bde1e45a27f.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/9e072907-4315-401a-b453-995ede7bef7e/5373572930.pdfIn PDF document text
    • https://0502d5d0-a0f5-47b8-bc1c-644c46e4e431.filesusr.com/ugd/6cabbb_7cf0277dd0d4409a803013f9477a4dd4.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/f1a84f22-e37b-44a1-9de4-b9a104457a0e/wetisujusunimarovudo.pdfIn PDF document text
    • https://9579f988-9383-433c-acf3-5fff76e0c882.filesusr.com/ugd/191a6d_fc3664bea8b3422f9f79751e9b662480.pdf?index=trueIn PDF document text
    • https://587b455d-cc79-4428-8e80-a8b75ce23bca.filesusr.com/ugd/021ec8_42829ab127ac46a4903f3d001626c069.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/4adcf318-4478-4c46-91c4-e707c64b6e31/toastmasters_table_topic_master_speech.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_off0000f112.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF112 5224 bytes
SHA-256: eb8ce20563a324852ede2def149c16de18ca6bec93beede7b71a8d1521150bca
font_01_sfnt_off000102c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102C6 10520 bytes
SHA-256: 4fda90668501568dfb2dc67f303660caa58f8bb6130c4a559573597ef1382e4e