Malicious PDF — malware analysis report

Static analysis result for SHA-256 f845ac0f8648ebae…

MALICIOUS

PDF

74.5 KB Created: 2021-09-20 00:10:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 9e55f3bf820915f08f808cea4d651644 SHA-1: 3a2a8e19d28c3ffc76ec8adbaae4c70fe037b7d2 SHA-256: f845ac0f8648ebae0a4e408a63fefdc33ad8b12761adb875cd58de59fdea40de
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to disposable hosting or compromised CMS upload directories, indicative of a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. No scripts were extracted, but the structure and URL analysis point to a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 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://koutingchina.com/upload/files/kanikena.pdf In PDF document text
    • http://girc.ncue.edu.tw/ckfinder/ckfiles/files/35322033932.pdfIn PDF document text
    • http://vanxuantravel.com/upload/files/pulatefesanizopuwifed.pdfIn PDF document text
    • https://g4m3s-4p1-12s1.com/contents/files/xasulinuf.pdfIn PDF document text
    • http://dtyxbpzx.com/filespath/files/20210903052513.pdfIn PDF document text
    • http://toeicspeaking.net/_UploadFile/Images/file/13690844922.pdfIn PDF document text
    • http://yasaitogo.com/uploads/files/kivukonamazuba.pdfIn PDF document text
    • http://dr-temt.ru/images/file/wonukalodezoxefa.pdfIn PDF document text
    • https://lmbri.com/WYSIWYGImage/file/53859391218.pdfIn PDF document text
    • http://autoklej.pl/app/webroot/media/files/raloxewiwex.pdfIn PDF document text
    • https://okazdedziecko.pl/_files/Media/file/wukuwazagesonobezodusizu.pdfIn PDF document text
    • https://12waktu.com/contents/files/6562411814.pdfIn PDF document text
    • http://scantech3d.com/files/84621349390.pdfIn PDF document text
    • http://bienbao.org/uploads/files/92589527850.pdfIn PDF document text
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/09c749e165d4682a9a32a4818f06827a/sujavepema.pdfIn PDF document text
    • http://carnavaldemarbella.com/Senegal_5/Content/files/userfiles/file/43866404136.pdfIn PDF document text
    • https://www.sevgiliyevideo.net/wp-content/plugins/formcraft/file-upload/server/content/files/161343ade3c9bf---guvulonopisiwori.pdfIn PDF document text
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614562dfbd0ca---93298832186.pdfIn PDF document text
    • https://masukpt2.com/contents/files/sifiropagilaw.pdfIn PDF document text
    • http://baheth24aqari.com/ckfinder/userfiles/files/liganakuneti.pdfIn PDF document text
    • https://nguyenhungstone.com/uploads/image/files/tadam.pdfIn PDF document text
    • https://defi128.com/userfiles/files/rimatiwigizirebopu.pdfIn PDF document text
    • http://zjgjqmr.com/v15/Upload/file/202192050568848.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=surya+namaskar+rattan+mohanPDF link annotation
    • http://s292376414.onlinehome.fr/datas/imgmail/file/zivogelolonaxemaraxiwab.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://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_off0000c030.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC030 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d847.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD847 10484 bytes
SHA-256: cbcbd89ffc1cbc96b59a725170504c0ea7cbe0a28e96d161a34232a3697f2b7b
font_02_sfnt_off0000eff5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFF5 16908 bytes
SHA-256: 53e9baf74e663383f5e07726d2cb84f7464d05499f3a36ab04761118aa8c8017