Malicious PDF — malware analysis report

Static analysis result for SHA-256 2bbbba4d46d4a9bc…

MALICIOUS

PDF

69.3 KB Created: 2021-09-26 15:32:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: f3eafbab333272a17aa4368d9a29dc26 SHA-1: 68230eb32fadbe8a7ed176f346fa2c8b09f01e04 SHA-256: 2bbbba4d46d4a9bca63a56fda2f7e5132e2363bc6f2463fc7589bc5d6db3b891
126 Risk Score

Malware Insights

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

The sample was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier as malicious. It contains numerous embedded URLs pointing to a link farm, with many of these URLs leading to other PDF files. The heuristic PDF_SEO_DISPOSABLE_LINK_FARM indicates a deliberate attempt to create a large number of links on disposable hosting, suggesting a phishing or malware distribution scheme. While no scripts were explicitly extracted, the nature of the PDF and its embedded links strongly suggests it is used as a lure to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • 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.
  • 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 https://chaletsuenodesol.de/files/93157523616.pdf In PDF document text
    • http://emannsltd.com/userfiles/99941814007.pdfIn PDF document text
    • https://aecvfcom.nrgence.com/upload/userfiles/files/39645787227.pdfIn PDF document text
    • https://clinicscrm.com/img/files/nuwebol.pdfIn PDF document text
    • https://elnativocoffee.com/silver/upload/files/24520261651.pdfIn PDF document text
    • http://cp-1.ru/userfiles/files/danawisejelimiwuwarajovef.pdfIn PDF document text
    • https://robert-zauer.cz/userfiles/file/sotegaxewogagubunamega.pdfIn PDF document text
    • https://www.ibyservice.com/wp-content/plugins/super-forms/uploads/php/files/679abdf796a2b96293d8885762ccc502/paxito.pdfIn PDF document text
    • http://shamayachts.com/upload/file/36034007954.pdfIn PDF document text
    • http://qlinairnv.be/userfiles/file/89892893734.pdfIn PDF document text
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16132ee0a8a24f---65701231667.pdfIn PDF document text
    • http://www.dr.schure.net/ckfinder/userfiles/files/pixupikixulolezajezes.pdfIn PDF document text
    • https://limadelimon.com/images/file/rivowobojinif.pdfIn PDF document text
    • http://agedwedfjtj.pretty-match.com/upload/files/sirosajadabunujun.pdfIn PDF document text
    • https://dcmheavyequipment.com/admin/images/file/devawamojogebitepasumape.pdfIn PDF document text
    • https://xtremefitksa.com/ckfinder/userfiles/files/letowarakarigaxupunupasuj.pdfIn PDF document text
    • http://lrm.mcdonalds.ua/ckfinder/userfiles/files/pafalukafoworirasokanulez.pdfIn PDF document text
    • http://nissanotogovap.vn/uploads/images/files/76124013305.pdfIn PDF document text
    • http://nationshield.ae/userfiles/files/folitat.pdfIn PDF document text
    • http://barudan.hk/UploadFile/file/20210919031304766.pdfIn PDF document text
    • https://ferropula.hr/files/19722082005.pdfIn PDF document text
    • http://efuegypt.org/userfiles/file/57584168950.pdfIn PDF document text
    • http://malagi.pl/user-files/fck/file/22374817608.pdfIn PDF document text
    • https://ooo-kenk.ru/userfiles/file/27780957386.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=device+restriction+settings+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_off0000afd7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAFD7 10564 bytes
SHA-256: 243bae726c6ab19d31ad01e768cbf2b6539a60c4442117a6f28ef95c6186d921
font_01_sfnt_off0000c7f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7F2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e004.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE004 15792 bytes
SHA-256: d1e334316f2c7594b1cdcf22175ea8901c4d8b5091ef4e40c2ff681fa9268a91