Malicious PDF — malware analysis report

Static analysis result for SHA-256 05cb130bb3b39019…

MALICIOUS

PDF

85.5 KB Created: 2021-09-17 06:34:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 61c18d5b4c58319ac47851ee11daf308 SHA-1: 955db5ee5c077e0e8245f250049bb73c6e90e035 SHA-256: 05cb130bb3b3901974e3e80578fda2c10bfb79810e05b06c2aebbde05b974b75
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, with many embedded URLs pointing to compromised or disposable domains. These links likely serve to redirect users to phishing sites or download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://cafemsoffice.com/userfiles/files/69723084318.pdf In PDF document text
    • https://arhstroi.by/uploads/files/44128266780.pdfIn PDF document text
    • https://hsegroup.ru/wp-content/plugins/super-forms/uploads/php/files/avbc8qt7o8a4b4b7cv0s8dneb5/puvanisajuxovumi.pdfIn PDF document text
    • http://kfnmdg.com/upfolder/e/files/20210913131209.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613720197e89b---3506879802.pdfIn PDF document text
    • https://ochronaskory.pl/pliki_user/File/86249266484.pdfIn PDF document text
    • https://thietbixaydungcantho.com/canthomobile2/public/images/sanpham/files/36947413224.pdfIn PDF document text
    • http://www.espace-hotelier.com/ckfinder/userfiles/files/fofal.pdfIn PDF document text
    • https://keluargamimpi.com/contents/files/nunigiwibutetexut.pdfIn PDF document text
    • http://lpkgoodframeupvc.com/userfiles/files/31420648504.pdfIn PDF document text
    • https://securitydm.eu/slicice/file/16464439173.pdfIn PDF document text
    • https://atasuorganiktarim.com/upload/ckfinder/files/1324650044.pdfIn PDF document text
    • https://chung-pei.com/userfiles/file/32766952813.pdfIn PDF document text
    • http://kargiskola.ge/myadmin/ckeditor/ckfinder/userfiles/files/69495649498.pdfIn PDF document text
    • http://sambometal.com/dataroom/file/puregefojo.pdfIn PDF document text
    • http://www.scmphotography.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161381cda44d60---1767190756.pdfIn PDF document text
    • http://infiniti.e-library.tw/uploads/files/demamitirevisamo.pdfIn PDF document text
    • https://mkserwis.pl/userfiles/file/jegat.pdfIn PDF document text
    • http://fortwashington.abwingsmd.com/uploads/files/mebimudizizulabimolenenob.pdfIn PDF document text
    • https://dom4m.de/userfiles/files/33406352794.pdfIn PDF document text
    • https://honkakuji.jp/honkakuji/images/ckfinder/files/rasupudibipemugunafoviw.pdfIn PDF document text
    • https://suativisamsungtaihanoi.net/upload/files/60271115611.pdfIn PDF document text
    • https://almuhja.ps/ckfinder/userfiles/files/84992717275.pdfIn PDF document text
    • http://igigeothermal.jp/userfiles/file/50896424523.pdfIn PDF document text
    • http://metabolit.ru/files/file/xogonabidulevawetufuwizij.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=standoff+2+system+requirements+androidPDF 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_off0000e5dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5DC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fdf3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDF3 11024 bytes
SHA-256: d9e5acd89c71268285b996895350c133516da7d278c486f9f2d29dd409ee1ca8
font_02_sfnt_off00011772.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11772 18424 bytes
SHA-256: f5a9f53a4546ddbeafc387b43cd9c25576cee1a7fe64dacf08237db8a66d2034