Malicious PDF — malware analysis report

Static analysis result for SHA-256 19b37a20b2350784…

MALICIOUS

PDF

86.1 KB Created: 2021-05-01 11:17:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 71087879fe175649c021a2ddfda5f50d SHA-1: 77f64307d093c4a85a785fbdcaef67507e4866d3 SHA-256: 19b37a20b2350784328def661c8cbc77558a1eb066cd80bdd4bbe4f2d6d4bdfc
186 Risk Score

Malware Insights

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

The sample is a PDF file identified as malicious by ClamAV and an ML classifier. It contains a significant number of external links, many hosted on disposable domains, suggesting a link farm designed to distribute malicious content or phish users. While no scripts were explicitly extracted, the PDF structure and numerous external URIs indicate a likely attempt to lure users to external sites, potentially for further exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://leonvi.ru/strik?utm_term=the+world+in+6+glasses+chapter+summaries PDF link annotation
    • http://firstreadersclub.com/sky_map_app_for_android_free_downloadl3zu4.pdfIn PDF document text
    • http://jekefidaz.mygamesonline.org/bixuwabe.pdfIn PDF document text
    • http://gavediteriremuv.medianewsonline.com/ahle_hadees_islamic_books_urdu.pdfIn PDF document text
    • http://majusenise.sportsontheweb.net/pipexulenuzuvatila.pdfIn PDF document text
    • http://life50it.pro/rozanikeledodetigisokgc8t3.pdfIn PDF document text
    • http://gonifarej.mywebcommunity.org/60637983600.pdfIn PDF document text
    • http://linunewilut.mywebcommunity.org/statistical_analysis_in_psychology_and_education.pdfIn PDF document text
    • http://vkysnaya-eda.site/are_transportation_costs_fixed_or_variabletlap3.pdfIn PDF document text
    • http://tb-films.ru/688334103894wkov.pdfIn PDF document text
    • http://xojuxelase.medianewsonline.com/45394649617.pdfIn PDF document text
    • http://jerabigemoz.sportsontheweb.net/apgli_application_form_12.pdfIn PDF document text
    • http://ligumexijigab.getenjoyment.net/62325630969.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/13d9b439-e7e1-4c14-b217-acd1090d3c1d/98936082643.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a6b51408-9472-4a1e-aeb6-0fa432d15b74/compaq_presario_cq57_drivers_for_windows_xp_free_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a2eb8833-0b58-44c4-9dd9-081bf5cf0876/zikevogifuvuf.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/25b8354b-293a-4879-8e70-500d57840e4b/best_free_video_making_app_for_pc.pdfIn PDF document text
    • https://24b051fc-04af-4e2d-8b9e-4e75c06063ec.filesusr.com/ugd/1a488c_2a0b356f2da7498c93836668b7c6cdf3.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/36f0badb-18b1-4659-a634-371d06c634a2/31936767047.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8c6b9e54-51c9-4c2a-8eb0-82ab34484fb1/fevukimaluganejafemosud.pdfIn PDF document text
    • https://8f0c9b82-9570-4081-bbb7-5e23a534ea09.filesusr.com/ugd/7008f3_cf0183b22e5d4acc90f42e86eb0d754e.pdf?index=trueIn PDF document text
    • http://xakazasaravi.onlinewebshop.net/haryana_assembly_election_2020_notification.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/de1149c6-e409-4b1c-a0b4-e5798711821b/52864482012.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c9262d41-6fd1-4f99-8c2a-449e973097dc/is_infrared_therapy_good_for_you.pdfIn PDF document text
    • https://d128792e-e0a8-46e0-98ed-b941f5da69b2.filesusr.com/ugd/b98abb_6182d93e5f0e4ccc9999c3d49a9f720b.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/413b126d-635d-4226-aefc-27a8b330f6f0/tantric_massage_quotes.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_off00010ff8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FF8 5684 bytes
SHA-256: 548961b3eae0a8fdef18c5d4fddd6bd4a9a0522ce08b4fba6616cb3daa5da7eb
font_01_sfnt_off00012331.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12331 11572 bytes
SHA-256: 10cac3bc66401f972c048c3a30a4bfce0884a2d81259ae9fe4be1cce648ae1fd