Malicious PDF — malware analysis report

Static analysis result for SHA-256 51e53af86b06b80f…

MALICIOUS

PDF

84.1 KB Created: 2021-05-22 12:07:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: 311bbc927da114b7705d8a94cd7cdcec SHA-1: 6bbdf48e700bc3cf4ff5617f55d221c2ad12238f SHA-256: 51e53af86b06b80f9c9fa0d5eaa67151ee3186dd154df84da2169fbfe3d7326a
214 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, with one critical heuristic identifying a link to known malicious redirector infrastructure. The document body, though heavily obfuscated, appears to be a lure related to IELTS preparation. The presence of a link farm and the ClamAV detection strongly indicate a phishing or scam campaign designed to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://yafferge.ru/strik?utm_term=how+to+get+8+bands+in+ielts+writing In PDF document text
    • https://cdn-cms.f-static.net/uploads/4366365/normal_5fe6bb602f817.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4377663/normal_5fcb275e7975e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4405945/normal_604a65b2a77ba.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4452834/normal_6061fe088c9bc.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4484807/normal_605f881c3cad2.pdfIn PDF document text
    • https://kuvakikarubefi.weebly.com/uploads/1/3/1/3/131383404/2905547.pdfIn PDF document text
    • https://xozugovapotup.weebly.com/uploads/1/3/1/1/131164024/pagafuxex.pdfIn PDF document text
    • https://zivexuxa.weebly.com/uploads/1/3/1/8/131871677/63959a6258e0.pdfIn PDF document text
    • https://bodobazanukabub.weebly.com/uploads/1/3/4/8/134889783/kuxekazolititip_mikeridena_tesugamava_tafuwijur.pdfIn PDF document text
    • https://bixagitiwor.weebly.com/uploads/1/3/4/6/134618264/pulirereg-pukefupiwiteneg-mapajew-molozerezid.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/kofabube/87360319005.pdfIn PDF document text
    • https://s3.amazonaws.com/zesixefe/kolors_weight_loss_diet_chart_in_tamil.pdfIn PDF document text
    • https://s3.amazonaws.com/megujobemegor/danaxam.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cbfb3ea3-b318-47ca-aed9-8de024da492c/96416394673.pdfIn PDF document text
    • https://s3.amazonaws.com/xamapebonijos/what_is_functional_grammar_in_hindi_language.pdfIn PDF document text
    • https://s3.amazonaws.com/wavunot/broughton_hall_uniform.pdfIn PDF document text
    • https://s3.amazonaws.com/fukezavazuj/runagadomexi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/45a57bb3-bcc6-42cf-b2f7-b504c6981c26/elementary_statistics_triola_12th_edition.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3c482de9-6e06-469f-886d-00ed443dc7b6/days_with_frog_and_toad_the_hat_comprehension_questions.pdfIn PDF document text
    • https://s3.amazonaws.com/wewiro/79398337694.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7bde8670-e707-4e4d-b7f6-77ee2c4cb990/jopujit.pdfIn PDF document text
    • https://s3.amazonaws.com/vokeri/avakin_hack_apk.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8b504919-fce2-4263-95fc-db4dc87d9c67/what_is_expository_and_example.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_off000109db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109DB 5380 bytes
SHA-256: 77faf6ae1960d69f3811c1bed86ebedd5cf202d88914e20b32a2de97ad43aff9
font_01_sfnt_off00011c40.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C40 11432 bytes
SHA-256: 982cc8b88bea205544cc2c0f8d29d189df50265da089773e08ab2758dbc7f5c6