Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac83649a59350483…

MALICIOUS

PDF

83.6 KB Created: 2021-09-17 22:56:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 061c5dd76b4fd0652015b189f0d796c7 SHA-1: dafc747f1205fb9b21258eb5a13d1a89897597c7 SHA-256: ac83649a5935048399776382360e1e93e24cea31222d916bb22e1746388a2e68
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF sample was flagged by multiple heuristics as containing a link farm pointing to compromised or disposable hosting. The ML classifier and ClamAV also identified it as malicious. The embedded URLs suggest an attempt to redirect users to external sites, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://parkergeneralcontractors.net/userfiles/file/woxozuxozuw.pdf In PDF document text
    • http://www.petercar0937494634.com/upload/img/files/zinokixiwefitesutapefudo.pdfIn PDF document text
    • http://fermobkorea.com/userfiles/file/20210911174926.pdfIn PDF document text
    • http://md-servicios.com/userfiles/file/gozubagemulisele.pdfIn PDF document text
    • https://mosconi.net/userfiles/file/bosuvadasosar.pdfIn PDF document text
    • http://www.primariasantana.ro/uploads/file/sotedusanabifewojow.pdfIn PDF document text
    • http://ckm-machinery.com/userfiles/files/semugelape.pdfIn PDF document text
    • http://nadiadsa.org/userfiles/file/zibezo.pdfIn PDF document text
    • http://gccde.com/downloads/blog/geust/files/fobozaf.pdfIn PDF document text
    • http://daydreamspin.com/userfiles/file/66924994721.pdfIn PDF document text
    • https://estatecambodia.com/htdocs/cljr/data/files/41325767742.pdfIn PDF document text
    • http://pcserviszlin.cz/ckfinder/userfiles/files/35245295634.pdfIn PDF document text
    • http://phuketdriveschool.com/userfiles/file/fesidebajobegebodife.pdfIn PDF document text
    • https://shirbandifelt.com/userfiles/file/10488913701.pdfIn PDF document text
    • https://saftanton.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16132835d3c1a8---xumazudo.pdfIn PDF document text
    • http://stl-hk.net/userfiles/murimuvu.pdfIn PDF document text
    • https://www.reparaciondebomba.com.ar/wp-content/plugins/super-forms/uploads/php/files/i2q2q8a79m4so7otfrr322tj00/vikifokiremita.pdfIn PDF document text
    • https://hantverksakuten.se/ckfinder/userfiles/files/jowaxajopo.pdfIn PDF document text
    • http://vipavtoufa.ru/wp-content/plugins/super-forms/uploads/php/files/362008ad677d4bafaa05b77c8de95a27/62680378361.pdfIn PDF document text
    • http://leruichem.com/upload/files/lijuwunitabajog.pdfIn PDF document text
    • http://msiutilities.biz/documents/30753649870.pdfIn PDF document text
    • http://www.badischer-kunstverein.de/ckfinder/userfiles/files/20348804435.pdfIn PDF document text
    • http://minhanh.com/files/99361692711.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=how+to+get+apple+emojis+in+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_off0000ddbf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDBF 10944 bytes
SHA-256: ee29f82e78a1257e18c3ca40fe0404fdc0af10a2d0f8f896e1647fc2110fbbc8
font_01_sfnt_off0000f6da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6DA 19360 bytes
SHA-256: e6493ff2b712dd1327e4f7cb67d7ff23e535ebecea3632da76831453b3f3f1cf
font_02_sfnt_off00012905.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12905 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1