Malicious PDF — malware analysis report

Static analysis result for SHA-256 1bc66af9a0aac927…

MALICIOUS

PDF

71.2 KB Created: 2021-09-28 22:11:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 03d8c488c0381b64181d6fd020c416de SHA-1: 526eaa47fd9594dc3f92fc92bbe5f0f040d19316 SHA-256: 1bc66af9a0aac927ff55f995860822dbffc715e0de47ed293f697a8b39436987
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file was identified as malicious by ML classifiers and ClamAV, with high-confidence heuristics indicating it is a link farm pointing to compromised WordPress uploads and disposable hosting. The PDF contains numerous external URIs, suggesting a phishing or malware distribution lure. No scripts were extracted, and the document body was unreadable, limiting further analysis of specific user-facing content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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 http://sitarofindiamd.com/userfiles/file/51119456524.pdf In PDF document text
    • https://rugsdirect4u.com/uploadedfiles/file/birudarawiveduluvamuzel.pdfIn PDF document text
    • http://gibisch.info/files/files/wabavasogumubonolixi.pdfIn PDF document text
    • https://petala.gr/userfiles/file/bopoxovijudijupewunagik.pdfIn PDF document text
    • https://nezamirekhaseafoods.com/userfiles/file/26870806819.pdfIn PDF document text
    • http://togclick.com/media/userFckfiles/file/nitasugibujibumeli.pdfIn PDF document text
    • http://goldway.jp/upload/board/file/lerurevefuk.pdfIn PDF document text
    • http://goldia.cz/data/file/pavaxixomopegamiwog.pdfIn PDF document text
    • http://www.corazondelsol.es/ckfinder/userfiles/files/lazimubigakov.pdfIn PDF document text
    • https://jlgardner.org/home/jlg/public_html/ckfinder/userfiles/files/27605947114.pdfIn PDF document text
    • http://nissan.e-library.tw/uploads/files/gomerefewodovovumosag.pdfIn PDF document text
    • https://qwert5.com/psum/admin/userfiles/file/kakupukafegunu.pdfIn PDF document text
    • http://www.jamesbgriffinlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ff9ae0e8cf---39554469713.pdfIn PDF document text
    • http://gd-weimi.com/upfolder/e/files/20210909085000.pdfIn PDF document text
    • https://hafa-verein.de/wp-content/plugins/super-forms/uploads/php/files/1bbbd9d94127c4e76e3619f026b0ec19/77492591613.pdfIn PDF document text
    • https://www.beadvised.co.uk/wp-content/plugins/super-forms/uploads/php/files/44e9dfd7c049e68036e75b96f02cf0b9/38011936437.pdfIn PDF document text
    • http://thesnowmanicecream.com/ckfinder/userfiles/files/49763057072.pdfIn PDF document text
    • http://naasschoolofmotoring.com/fckeditor/userfiles/file/jodajikopidikejewagow.pdfIn PDF document text
    • https://joebalogh.ro/imagini_ws/fiwaguvofemasuna.pdfIn PDF document text
    • http://edilcfcostruzioni.com/userfiles/files/15013661037.pdfIn PDF document text
    • https://dhins.com/testingsites/advantage_aviation/assets/media/file/difeve.pdfIn PDF document text
    • https://www.eos.org.eg/ckfinder/userfiles/files/peligakejaru.pdfIn PDF document text
    • http://themadthinker.com/temp/vinney/HTML/userfiles/file/gubudovipi.pdfIn PDF document text
    • http://didula.com/img/file/rejujuzitizetamobuz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=how+to+transfer+files+from+phone+to+memory+cardPDF 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_off0000b41c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB41C 11076 bytes
SHA-256: c7598cdcbe944e18479bb8e624531d5603606620cbf04cf3b69f6cac26f9359a
font_01_sfnt_off0000cdbd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDBD 16048 bytes
SHA-256: 178c71c5984d72eb68b716d61589c78eba820d6d1b934926bbcd4721288a66f7
font_02_sfnt_off0000f675.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF675 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1