Malicious PDF — malware analysis report

Static analysis result for SHA-256 77b73e642a964507…

MALICIOUS

PDF

82.6 KB Created: 2021-09-20 10:32:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 44374835b06c58c1dd75c0eb49efd446 SHA-1: 83e3789571f177e903adc4be99504df8bb65927e SHA-256: 77b73e642a9645072924f4d07b4f1cd773036808feb6a4ede1a6ebf592bade60
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, and exhibits characteristics of a callback phishing lure. While no scripts were explicitly extracted, the PDF structure and embedded URLs suggest it is designed to redirect users to potentially malicious sites or prompt them to call fraudulent numbers. The presence of numerous unknown URLs further supports a phishing or scam attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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 http://vladjurnalist.ru/archive/file/44451166850.pdf In PDF document text
    • http://pensjonatagat.pl/userfiles/file/3474231089.pdfIn PDF document text
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134e2701aa82---1135285933.pdfIn PDF document text
    • http://koreabulk.net/userData/board/file/33368636453.pdfIn PDF document text
    • http://rebizplus.com/userfiles/file/86478355274.pdfIn PDF document text
    • https://intrastorg.com/userfiles/file/rukabot.pdfIn PDF document text
    • https://renfrewareahealthvillage.ca/ckfinder/userfiles/files/41512977118.pdfIn PDF document text
    • http://www.culturehousesun.org/photos/file/71323856624.pdfIn PDF document text
    • http://textingrights.com/userfiles/files/miwobemuri.pdfIn PDF document text
    • http://zima.italie-ubytovani.cz/data/file/bokabifegorema.pdfIn PDF document text
    • http://baraanduliaptti.org/userfiles/file/lenawunevugozevelu.pdfIn PDF document text
    • https://quanticabtl.com/cms_2018_quantica/sgi_userfiles/userfiles/files/92427343296.pdfIn PDF document text
    • https://erdenetpost.mn/userfiles/files/dubifogiselozukejekas.pdfIn PDF document text
    • https://drakbera.com/ckeditor/ckfinder/userfiles/files/39215546864.pdfIn PDF document text
    • https://successalpha.team/upload/files/wununukalomojazasa.pdfIn PDF document text
    • http://15881588.com/ckupload/files/13537806620.pdfIn PDF document text
    • http://cavusofis.com/images_upload/files/16568133926.pdfIn PDF document text
    • https://marathonroller.com/userfiles/files/gubemasonuzusesopa.pdfIn PDF document text
    • https://lotusmarinevn.com/upload/files/vugubofipazibaxivajifejos.pdfIn PDF document text
    • http://www.jamesbgriffinlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/161440b544c2ca---deretoxelurakidemozov.pdfIn PDF document text
    • https://apelhijau.com/contents/files/92454846668.pdfIn PDF document text
    • http://www.findvoters.com/userfiles/file/lemekeliveman.pdfIn PDF document text
    • http://bookblog.kr/data/file/files/30206334492.pdfIn PDF document text
    • http://christ-china.com/filespath/files/20210920123707.pdfIn PDF document text
    • http://goldmustang.ru/files/files/vujopiz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=ds+tunnel+vpn+apk+downloadPDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000de09.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE09 17688 bytes
SHA-256: e7f4307643e43be10d2d5b1e9af43f9410a6d3711c7812007cc813f52e325465
font_01_sfnt_off00010c47.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C47 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001245e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1245E 10540 bytes
SHA-256: afbe05daaebc8c75312c186cbb8c158a549d1941897733dcc0a50ec2a2dfe489