Malicious PDF — malware analysis report

Static analysis result for SHA-256 3d159d65be7b9e39…

MALICIOUS

PDF

71.0 KB Created: 2021-03-12 20:02:49 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-20
MD5: 05531cd2ea167946a049619493e03e92 SHA-1: ed19d5a9f4ff3d069153edd659fa763373074959 SHA-256: 3d159d65be7b9e396ffcef59a65c443b15319d7951a010a2081dbf580871ae7e
244 Risk Score

Malware Insights

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

This PDF file is identified as malicious by multiple heuristics and a machine learning classifier, specifically flagged as a phishing trojan. It contains a large number of embedded URLs, forming a link farm designed to redirect users to potentially malicious sites, including a known malicious redirector. The document body, though heavily obfuscated, contains text related to 'spoken english classes' which likely serves as a lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://dafemum.ru/wb?keyword=spoken%20english%20classes%20in%20nugegoda In PDF document text
    • http://brettlockhart.com/13725526966qgrmn.pdfIn PDF document text
    • http://top-odejda.com/balupu_telugu_movie_hd_video_songstwd4h.pdfIn PDF document text
    • https://cdn.sqhk.co/naxupowu/gsmlgjr/extreme_crash_car_driving.pdfIn PDF document text
    • http://kasaxeko.mypressonline.com/miruxokarutexojow.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4408582/normal_5ff345aa2aaba.pdfIn PDF document text
    • http://physcoo.com/vejugopaniwomulezeferofos1w9gm.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4487192/normal_600ae5485f87c.pdfIn PDF document text
    • https://dukagalirizaz.weebly.com/uploads/1/3/1/8/131856141/4397504.pdfIn PDF document text
    • https://cdn.sqhk.co/bajowekununa/ic5hdKo/xowalowefevetul.pdfIn PDF document text
    • https://sukodijam.weebly.com/uploads/1/3/4/5/134516983/6754747.pdfIn PDF document text
    • https://cdn.sqhk.co/vozogekom/e9Vqtjh/98845685060.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4366668/normal_5fde8a6951ab8.pdfIn PDF document text
    • https://cdn.sqhk.co/nebafori/Uaibbhc/border_patrol_officer_become.pdfIn PDF document text
    • https://pajejasebuwosiw.weebly.com/uploads/1/3/0/8/130813778/8033f436851de54.pdfIn PDF document text
    • https://povutepumik.weebly.com/uploads/1/3/2/7/132741486/vozawakupo.pdfIn PDF document text
    • http://latencfsrt.space/fundamentals_of_thermodynamics_9th_eox3tg.pdfIn PDF document text
    • https://cdn.sqhk.co/notudubugu/igZRjOr/reading_comprehension_worksheets_for_6th_grade_students.pdfIn PDF document text
    • https://cdn.sqhk.co/manaruparil/janoOgc/28416059700.pdfIn PDF document text
    • https://madumowa.weebly.com/uploads/1/3/2/7/132710776/8833575.pdfIn PDF document text
    • https://cdn.sqhk.co/labifikup/gZvhzJl/the_chosen_merch_calendar.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://vimixof.onlinewebshop.net/how_do_you_know_if_your_flame_sensor_is_bad.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_off0000d61b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD61B 5404 bytes
SHA-256: 6334e20dd51078863197892798ff8e7478f578f1dbafc5c6403bfa0713afddf3
font_01_sfnt_off0000e884.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE884 10908 bytes
SHA-256: 719797db4e43b34fe5fa0cf31d94440d06b19fff740a55aa618770cec127f160