Malicious PDF — malware analysis report

Static analysis result for SHA-256 5fb04f51523838d5…

MALICIOUS

PDF

76.0 KB Created: 2021-03-22 19:44:15 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-13
MD5: ca526b76738b944de1c9dd56bfd84706 SHA-1: cbd2ed84e1653b57dc32367955bc98fc97bee4f4 SHA-256: 5fb04f51523838d58a7c4b37f8b06db18a405fd96cf4b56d8ef539d65edc8b1f
186 Risk Score

Malware Insights

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

The PDF file contains numerous external links, many pointing to disposable domains and likely part of a link farm for SEO manipulation or to host malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body, though heavily obfuscated, contains keywords related to 'Abraham Lincoln biography PDF' and application metadata suggesting it was generated by wkhtmltopdf, a tool often used to create SEO spam or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://vilenefex.ru/award?keyword=abraham+lincoln+biografia+pdf PDF link annotation
    • http://fortuneocredit.com/732027169002csh5.pdfIn PDF document text
    • http://onlineeshop24.xyz/thinkorswim_desktop_app_not_workingyqjiq.pdfIn PDF document text
    • http://podcard2020.site/34359124109ulf64.pdfIn PDF document text
    • https://jepejopik.weebly.com/uploads/1/3/4/6/134610321/33dd4287525.pdfIn PDF document text
    • https://bozixezexa.weebly.com/uploads/1/3/4/8/134861503/tuzegutolejan-rapadatosuf-xusivinif.pdfIn PDF document text
    • http://prodson.fun/relationship_skill_building_worksheetsrdb9v.pdfIn PDF document text
    • https://ruwatija.weebly.com/uploads/1/3/4/8/134846771/xokejunepiturij_gelujemomogesaf_golewiwe_batosa.pdfIn PDF document text
    • https://jatufajikovuna.weebly.com/uploads/1/3/4/7/134719937/xudejurixober.pdfIn PDF document text
    • http://aicberg.net/20938645111ebax8.pdfIn PDF document text
    • https://vogaxuruxav.weebly.com/uploads/1/3/4/3/134352923/tuwivavidikok.pdfIn PDF document text
    • https://lewuroluloxujul.weebly.com/uploads/1/3/4/6/134678017/zidoruti.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/b6f78768-771c-4df7-807e-ab68ab01ae20/which_of_the_following_is_considered_a_strong_acid.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2e5d7e68-1aa3-4951-b25e-f8fe1141243a/is_there_a_reset_button_on_a_whirlpool_dishwasher.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9938306b-de52-4820-9573-bc2c72345d7a/how_do_you_know_if_a_car_seat_is_faa_approved.pdfIn PDF document text
    • https://729282ec-1290-4cbc-9302-cf8a24acd4c7.filesusr.com/ugd/42c189_984117f92ed64e60a1cef07232d1681f.pdf?index=trueIn PDF document text
    • https://4cd5a77a-be8d-44ba-8952-4177873115c4.filesusr.com/ugd/930050_43236371ffae4f2884a51a47dbfdd739.pdf?index=trueIn PDF document text
    • http://doriponesarom.myartsonline.com/how_to_know_when_to_enter_a_trade_in_forex.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c8d5538b-4200-4d1d-94ef-db8d65443588/suzuki_cello_book_1_slideshare.pdfIn PDF document text
    • https://ececae0b-1312-4a4c-959a-117928b3d478.filesusr.com/ugd/e6721e_9471a70d0f594a019064cbe5c5791318.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/3ef8cac7-c042-4c2a-a2a7-e136e8220568/which_fitbit_quiz.pdfIn PDF document text
    • http://pevipitoz.atwebpages.com/febowo.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_off0000eb95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB95 5520 bytes
SHA-256: 18ae3ddb31f0f07fb2fcfd97c137f9ec4796454bb73e4fd9b00d1fe78ea189d1
font_01_sfnt_off0000fe2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE2D 10656 bytes
SHA-256: 5f35b486b7d226769731a17ffc0d4865a6745305f7ff6d221069bb7a69061f8a