Malicious PDF — malware analysis report

Static analysis result for SHA-256 a335cb427f1888e8…

MALICIOUS

PDF

114.5 KB Created: 2021-10-06 00:19:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: dd1a9a071714e14df44563af6c2332de SHA-1: f599b31e3dda57773b27fbc378fefd0a9fe92b64 SHA-256: a335cb427f1888e869b45f9b3d31666683735bc150f3145de9852c6bf30b0700
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many pointing to compromised or disposable domains, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. The file's structure and numerous external links align with techniques used to obscure the ultimate destination of malicious payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9943

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 https://ghnservizi.com/file/rinebas.pdf In PDF document text
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/09275bcc6a87e59c8f890e0b43cf8562/28066988352.pdfIn PDF document text
    • http://pnlestari.com/visitbali/image/files/82842213642.pdfIn PDF document text
    • http://bochkari24.ru/pic/file/56816921244.pdfIn PDF document text
    • http://poltinik.ru/userfiles/file/46902944089.pdfIn PDF document text
    • http://champaigncursillo.com/userfiles/file/16641341590.pdfIn PDF document text
    • https://sagarexpress.com/userfiles/file/sovumego.pdfIn PDF document text
    • http://uat2.hkha.com.hk/ckfinder/userfiles/files/vixutezexanipes.pdfIn PDF document text
    • https://sensesgrouphk.com/louis/STARKGROUP/ckfinder/userfiles/files/15155989283.pdfIn PDF document text
    • http://camberwelltaxi.com/survey/userfiles/files/mupexinexegomilutigesub.pdfIn PDF document text
    • http://pathtojanna.com/userfiles/files/susafibiwoxiwunaliguvor.pdfIn PDF document text
    • http://saimiri.name/upload/file/2886155482.pdfIn PDF document text
    • https://mtdind.aicsmindia.org/ckfinder/userfiles/files/duwetapiz.pdfIn PDF document text
    • http://auxerretv.com/content/public/file/zuzugutulutinululuwi.pdfIn PDF document text
    • http://limeitec.com/upfiles/editor/files/40581337707.pdfIn PDF document text
    • http://www.insurancedirectcanada.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1614155cfe4ffe---miwobigoxo.pdfIn PDF document text
    • http://www.electricman.in/demo/frontend/web/uploads/files/74278002241.pdfIn PDF document text
    • https://riverasphotovideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/161450ea01524f---88084082760.pdfIn PDF document text
    • https://www.renouer-auxerre.com/ckfinder/userfiles/files/98438197448.pdfIn PDF document text
    • https://dsverano.com/UserFiles/File/66160532123.pdfIn PDF document text
    • https://cobrawire.com/userfiles/files/jefunakenupofibupipok.pdfIn PDF document text
    • http://kechengchem.com/upload/files/xovizokum.pdfIn PDF document text
    • http://balletpanov.com/uploads/files/lexedudafupopof.pdfIn PDF document text
    • https://www.entornopublicitario.com/wp-content/plugins/super-forms/uploads/php/files/6df1bf48886ac7d81409836d3db61645/76635980270.pdfIn PDF document text
    • https://shiokuda2.com/contents/files/70919113789.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=kowloon+city+walled+parkPDF 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_off0001514f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1514F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00016961.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16961 23008 bytes
SHA-256: b0220f15c0bde9902afd2e89bbf856fe5dded443db81752bf25e87eb56423b61
font_02_sfnt_off0001a415.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A415 10620 bytes
SHA-256: f79b6dce2b255a7ade2b49a4c088eb7d88fec27ea106c5cc3257fd7c45285262