Malicious PDF — malware analysis report

Static analysis result for SHA-256 b69c985c3b21096d…

MALICIOUS

PDF

74.0 KB Created: 2021-03-21 10:43:03 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-13
MD5: 1b9e488793164f06bf87b28f2d53b7a7 SHA-1: 4117b45896a1ff0752def16c7e371482489c2424 SHA-256: b69c985c3b21096d3cf8b7e837720e7ca8c2e2bd82e7472d2e28ecc884987fda
186 Risk Score

Malware Insights

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

This PDF file was identified as malicious by multiple heuristics and a machine learning classifier. It contains a large number of external links, many pointing to disposable hosting, suggesting a link farm or SEO manipulation tactic. One of the primary URLs extracted is https://pelibifir.ru/strik?utm_term=countable+and+uncountable+nouns+7+esl, which is likely part of a phishing or malware distribution scheme. No scripts were extracted, but the PDF structure itself facilitates the redirection to these external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://pelibifir.ru/strik?utm_term=countable+and+uncountable+nouns+7+esl PDF link annotation
    • https://tezilejesitox.weebly.com/uploads/1/3/1/1/131163634/kilujeleku_gasexunimoru_moteba.pdfIn PDF document text
    • http://mujepojubum.22web.org/33765208085.pdfIn PDF document text
    • https://vusokozederik.weebly.com/uploads/1/3/4/9/134901716/4303874.pdfIn PDF document text
    • http://nudekebe.iblogger.org/47366712344.pdfIn PDF document text
    • https://cdn.sqhk.co/rajemaramiw/bYajhTz/samsung_alpha_phone_case.pdfIn PDF document text
    • https://voruvagozi.weebly.com/uploads/1/3/4/7/134742827/kikuxusirek.pdfIn PDF document text
    • https://cdn.sqhk.co/reretukida/WjgChjd/blank_calendar_format.pdfIn PDF document text
    • https://fezowekufeda.weebly.com/uploads/1/3/3/9/133999429/db321502b.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://rokejunikutigid.rf.gd/65554925694.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/55880013-bab4-44b4-a205-0c586a8d64b9/how_to_pass_the_aswb_masters_exam.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/31f30b29-1603-4820-8424-afb82ae6cfb1/schwinn_airdyne_ad4_windscreen.pdfIn PDF document text
    • https://bf130ee1-1463-4c69-9604-1b23772ced92.filesusr.com/ugd/b4609a_3f4f15d68a60485db31374c0c64670fc.pdf?index=trueIn PDF document text
    • http://kujujonagojatu.epizy.com/sound_effect_doorbell.pdfIn PDF document text
    • http://lagarudu.epizy.com/48130671294.pdfIn PDF document text
    • https://s3.amazonaws.com/vezumobigodub/cbse._nic._in_2019_date_sheet_class10.pdfIn PDF document text
    • https://6997f972-013f-4c6f-ac95-4179ba17a557.filesusr.com/ugd/549e1a_4fa6aedcc4b1475f8fcf367a1ecbcbfa.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/pavujiniz/35489020631.pdfIn PDF document text
    • https://s3.amazonaws.com/vezumobigodub/fabiziwi.pdfIn PDF document text
    • https://1c019786-7048-4615-837a-ae53f087c4ae.filesusr.com/ugd/8b4172_022f464d5c184cbead120c2da7d9bdbd.pdf?index=trueIn PDF document text
    • https://78e27e65-9996-4239-a63d-7a21722db537.filesusr.com/ugd/03f576_66f65314528f4b5781d521e26c8742bd.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/356f567e-9c9e-4d1e-b5a3-d8b65732d370/does_kroger_sell_blood_pressure_cuffs.pdfIn PDF document text
    • https://4b4b92a8-4ac5-4030-97d5-af0917f8c077.filesusr.com/ugd/0251f0_5be7a9d66af5442eae973c7bb4dc9fa5.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/bfc4c0cf-4333-4075-8b19-18865b8e51cf/xisowozovewefuvi.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_off0000e41d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE41D 4964 bytes
SHA-256: ebcb8beffbd2cd1fd0f0d8c944bd925c87871bb7cfc2b7d1ee0f3e5053c1eada
font_01_sfnt_off0000f50b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF50B 11156 bytes
SHA-256: ad7951c98f4278a77da18173f7e87d307115e4a16591e154b77b4127d4658c2e