Malicious PDF — malware analysis report

Static analysis result for SHA-256 a16ccb7b5da5b848…

MALICIOUS

PDF

74.8 KB Created: 2021-04-29 22:09:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-22
MD5: ea1fdff821207444f1a8c16e14414be2 SHA-1: dd5b8e82ba9fe21892374d69e0d36984dd042514 SHA-256: a16ccb7b5da5b848b67221838202bcf80e8043887c61315de64f91763ecc7676
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://nipisod.ru/strik?utm_term=does+cpap+help+blood+oxygen+levels PDF link annotation
    • https://cdn.sqhk.co/zeliravepuj/iXYvNIh/3887347571.pdfIn PDF document text
    • https://cdn.sqhk.co/lixipadiwel/ghifha2/amazon_kindle_unlimited_subscription_offer.pdfIn PDF document text
    • https://cdn.sqhk.co/retesixabe/fY2Usjf/bounce_ball_chair_benefits.pdfIn PDF document text
    • http://pelabinowoguk.getenjoyment.net/44526766360.pdfIn PDF document text
    • https://cdn.sqhk.co/zibomevuguli/AHDgcgf/impulse_response_convolution_reverb.pdfIn PDF document text
    • https://navemozozaju.weebly.com/uploads/1/3/1/1/131164567/4135773.pdfIn PDF document text
    • http://kurametugugu.mygamesonline.org/fejexo.pdfIn PDF document text
    • https://cdn.sqhk.co/rekubapapup/jjjed3p/80554302343.pdfIn PDF document text
    • https://tapidokebijimub.weebly.com/uploads/1/3/4/5/134577153/a8d088c9bb25f.pdfIn PDF document text
    • http://xuritepizib.mygamesonline.org/publicidad_coca_cola.pdfIn PDF document text
    • http://bitoxifa.sportsontheweb.net/using_if_function_in_excel.pdfIn PDF document text
    • https://gofexuzadefedim.weebly.com/uploads/1/3/4/3/134306088/4379187.pdfIn PDF document text
    • http://pebunoguge.mygamesonline.org/25290729876.pdfIn PDF document text
    • https://bujetukojijem.weebly.com/uploads/1/3/4/8/134875379/9a016de480feb.pdfIn PDF document text
    • https://sesifubonimexa.weebly.com/uploads/1/3/5/3/135317238/raguzeta.pdfIn PDF document text
    • https://zetoruribafepa.weebly.com/uploads/1/3/1/4/131452904/5564421.pdfIn PDF document text
    • http://zijofazasogija.getenjoyment.net/free_car_service_manuals.pdfIn PDF document text
    • https://kaxusumolen.weebly.com/uploads/1/3/4/5/134597517/sopekujufux_muvukalomi_periguzosipaset_vezatavanamu.pdfIn PDF document text
    • https://midumusifefo.weebly.com/uploads/1/3/5/4/135401272/wegokikoji.pdfIn PDF document text
    • https://papenuxid.weebly.com/uploads/1/3/0/8/130874395/soregasuzelan_jajekabut.pdfIn PDF document text
    • http://tepugorotewole.medianewsonline.com/vudegibuzezemejubak.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/99fa6026-59fe-4350-a670-c0eebde9c5da/ethical_issues_in_psychological_testing_wikipedia.pdfIn PDF document text
    • http://jadukubilelib.myartsonline.com/26780894226.pdfIn PDF document text
    • http://gexegubiduw.atwebpages.com/instant_academic_skills.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/75f63644-a68b-4fc8-b710-d6a98992a043/tibifibumudokazobuniz.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/54a52779-5efa-4c71-a420-6cf97acee1c0/how_do_i_set_the_time_on_my_casio_edifice_watch.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_off0000e44d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE44D 5608 bytes
SHA-256: b2c844f085131e89fd1450f0a1542af2ce04a7a84ca46ac2fcaa8f7f075117cf
font_01_sfnt_off0000f777.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF777 11344 bytes
SHA-256: 90a6a8ad5c607f3740fa68f60a327853c1e811568c4b9f435f297a8e920271c2