Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8f57c951ae904a7…

MALICIOUS

PDF

74.9 KB Created: 2021-06-09 10:08:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: c1d414a082f5d98f3bdeea72ffc25987 SHA-1: ceb43a1b98c1213cec1c0a0676a9fe7fce0f2490 SHA-256: b8f57c951ae904a75fb693d4e312d18ade3fdcca1ef70374020dd607aed5b50c
186 Risk Score

Malware Insights

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

The PDF file contains a link farm with 30 external links, many hosted on disposable domains, suggesting a phishing or malware distribution attempt. The embedded URLs, such as 'https://chcial.ru/pbw?utm_term=instagram+hack+account+no+human+verification', indicate a lure related to hacking Instagram accounts. The ML classifier and ClamAV detection strongly support the malicious nature of this file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://chcial.ru/pbw?utm_term=instagram+hack+account+no+human+verification PDF link annotation
    • https://lekibuwowobaveg.weebly.com/uploads/1/3/5/2/135295955/pigelokenimiv.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4486994/normal_603f52626994c.pdfIn PDF document text
    • https://kabirajozef.weebly.com/uploads/1/3/2/7/132740353/56a4ced3ba.pdfIn PDF document text
    • https://jitojadafolad.weebly.com/uploads/1/3/4/4/134404030/jejugeziseto_mexobimenurarav_kokujonif.pdfIn PDF document text
    • https://liwojugimigazip.weebly.com/uploads/1/3/4/9/134904469/8722772.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4407066/normal_60494c8463f54.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4444885/normal_6037efa8a4f98.pdfIn PDF document text
    • https://kaxebovirufuj.weebly.com/uploads/1/3/4/3/134399635/960449.pdfIn PDF document text
    • https://dotijude.weebly.com/uploads/1/3/0/7/130740148/fuwezusemavez-gelaginapusora-fokudavenupox-nagokepamaron.pdfIn PDF document text
    • https://seruliwosudaz.weebly.com/uploads/1/3/4/4/134457931/runopiziwujupij.pdfIn PDF document text
    • https://wozukepob.weebly.com/uploads/1/3/4/0/134017809/daxolujewiv.pdfIn PDF document text
    • https://rutedidatares.weebly.com/uploads/1/3/4/4/134490949/viruzakivudanufepi.pdfIn PDF document text
    • https://gedorizifoxe.weebly.com/uploads/1/3/1/6/131607240/bapofujoje_namugolasopifu.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://lodenapokot.pbworks.com/f/how_to_do_a_giveaway_on_instagram.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7c1bd020-f1d2-4d53-8a35-e027f92f23a6/85097754831.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9f0ca46d-80e8-45b6-803c-aee940cb1333/how_to_learn_cad_design_for_free.pdfIn PDF document text
    • http://wotasaful.pbworks.com/w/file/fetch/144567888/virtual_dj_2021_free_download_mac.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/18f00a2e-442a-4b53-895d-e302a20ffeec/67063338791.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8ddc4f52-5d39-4e67-970a-374513eaf42e/how_to_program_castle_creations_esc.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ecccd720-a90c-4013-9935-15b84815fb13/q_center_uconn_stamford.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3cc28564-11bc-4497-94b9-82f6b847156c/karcher_power_washer_rebuild_kit.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/765ce318-436f-4cc1-97fd-d3ea0d91ecfd/mutant_and_masterminds.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/15c1c81d-6771-4e5b-8798-7cbcd4f08081/all_you_need_to_know_about_the_music_business_audiobook_free.pdfIn PDF document text
    • http://zeranagaro.pbworks.com/w/file/fetch/144713559/abnormal_child_psychology_7th_edition_test_bank.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_off0000e717.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE717 5324 bytes
SHA-256: 9a77654777fbd2d4e384151b6f0bd222c3c1e0c3c3464cbf0101dd0e736aa5e3
font_01_sfnt_off0000f915.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF915 10612 bytes
SHA-256: cee67f57282a99be10568bed2d228d0e96db70c5d7327453316c19c7d8733b6f