Malicious PDF — malware analysis report

Static analysis result for SHA-256 fa8248819d76fc7e…

MALICIOUS

PDF

70.2 KB Created: 2021-09-28 01:24:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 4b5ebfed309433874607d1e3dacfd606 SHA-1: 9c6aa2c52ae9f37aa094e18485ec8367fa9f8642 SHA-256: fa8248819d76fc7eeebb8e293cfe3a2c588c8c9c449526f94ed7f4150fcbe03b
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristic 'SE_CALLBACK_LURE' strongly suggests a callback phishing or tech-support scam, where the document likely prompts the user to call a fraudulent number. While no scripts were extracted, the PDF structure and embedded URLs point towards a social engineering attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 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://kimsanghun.com/upload/userfiles/file/2021913648106308.pdf In PDF document text
    • http://damnoen.com/ckfinder/pho/files/pobimewuk.pdfIn PDF document text
    • http://materialdeestudo.top/userfiles/files/83281970594.pdfIn PDF document text
    • https://wroclawmodelshow.pl/ckfinder/userfiles/files/xefije.pdfIn PDF document text
    • http://geostudio.eu/userfiles/files/65875013781.pdfIn PDF document text
    • http://romento.com/uploaded_files/userfiles/files/80664366140.pdfIn PDF document text
    • http://poney-club-romilly-aigre28.fr/userfiles/file/japoridaberobidej.pdfIn PDF document text
    • http://www.oe.com.tw/ezadmin/ckfinder/userfiles/files/58216894691.pdfIn PDF document text
    • http://www.frank-diagn.hu/userfiles/files/40441988271.pdfIn PDF document text
    • http://fatamorgana.fr/uploads/assets/file/kalar.pdfIn PDF document text
    • http://aquarium-kochi.com/app/webroot/ckfinder/userfiles/files/69122264513.pdfIn PDF document text
    • https://holcom-wd.com/webroot/img/files/84015950730.pdfIn PDF document text
    • http://kubablimel.pl/Image/files/82131318945.pdfIn PDF document text
    • http://www.kevimotor-rock.hu/files/files/26984692039.pdfIn PDF document text
    • http://logisticsnetworks.net/ckfinder/userfiles/files/89031005169.pdfIn PDF document text
    • http://gzbaosui.com/uploadfile/files/rexude.pdfIn PDF document text
    • https://esperanzadeavila.com/fotos/file/96662500803.pdfIn PDF document text
    • https://weborder.cloud/userfiles/file///vagew.pdfIn PDF document text
    • https://www.unicodesystems.com/wp-content/plugins/super-forms/uploads/php/files/ur8101ug4d3q7jn0mf687rueh6/sidodil.pdfIn PDF document text
    • http://tdsns.ru/userfiles/file/35828179598.pdfIn PDF document text
    • http://chiron-ventures.com/chiron/home/img/upload/files/210907123456733316n946l.pdfIn PDF document text
    • http://mexvp.com/ckfinder/userfiles/files/sewilitagojapaluziwazeru.pdfIn PDF document text
    • https://limberhurstgallery.com/imageuploads/file/32706815050.pdfIn PDF document text
    • https://ambient-interier.cz/files/files/64347449163.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=how+to+bypass+google+account+on+android+phonePDF 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_off0000b0e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB0E5 11224 bytes
SHA-256: 7b2c4e8ec17bf6c29e09e6334eed914a4a6b7df7b3b91ff4da6468d06f9c93b8
font_01_sfnt_off0000cabf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCABF 15928 bytes
SHA-256: 0f05904a01dce2487e90c453593f5b6ccbe5c832d1a2b9ee02ccb4d2057f11e8
font_02_sfnt_off0000f321.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF321 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1