Malicious PDF — malware analysis report

Static analysis result for SHA-256 5c3d723fb601b253…

MALICIOUS

PDF

84.6 KB Created: 2021-09-18 20:12:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: e3d24d809a4581e7082bc6dcfdc92010 SHA-1: ed5e253265ed061e3e055d60b86e59b7d0264b35 SHA-256: 5c3d723fb601b253692d3be56ee8c0380343044f5c84a3fb73563c47ce0e7b8c
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, with several pointing to compromised CMS uploads and disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The presence of multiple external URIs and link farms points towards an attempt to lead the user to a malicious site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

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://flairpens.ru/uploads/files/79804611565.pdf In PDF document text
    • http://studiofranzoni.eu/userfiles/files/wibaguzawaw.pdfIn PDF document text
    • https://ww150004.linebot.net/upfile/files/20210904064934.pdfIn PDF document text
    • http://lejonhund.com/upload/47544133206.pdfIn PDF document text
    • https://voolabs.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614121671d558---puvuvusegidezowuxujo.pdfIn PDF document text
    • http://www.tractortools.cz/ckfinder/userfiles/files/wupakigavedopugana.pdfIn PDF document text
    • http://studiorestagno.eu/userfiles/files/36182447803.pdfIn PDF document text
    • http://angelescare.com/userfiles/file/93252321606.pdfIn PDF document text
    • http://veterinariogiardinelli.it/userfiles/files/jikapuwuzaxuju.pdfIn PDF document text
    • http://extintoresorigen.com/images/editor/dojoligiduxivage.pdfIn PDF document text
    • https://bancodevida.com/bancodevida/admin/images/image/file/98408461169.pdfIn PDF document text
    • https://dampinggame.com/calisma2/files/uploads/36574297035.pdfIn PDF document text
    • https://fortworthdental.net/cmsCart/upload/file/62308446176.pdfIn PDF document text
    • http://chronocertif.com/userfiles/file/44402499059.pdfIn PDF document text
    • http://greece-ex.com/images/blog/file/77270241070.pdfIn PDF document text
    • http://cnmrobotics.com/files/files/8938492695.pdfIn PDF document text
    • https://skyfireconsulting.com/wp-content/plugins/super-forms/uploads/php/files/vl5036hil8nsk74thou00ph6h0/kalosapinadep.pdfIn PDF document text
    • https://luathoanghuy.com/uploads/files/kijitet.pdfIn PDF document text
    • http://bjdfszwy.com/filespath/files/20210911185108.pdfIn PDF document text
    • https://hatinhjobs.com/upload/files/timumeremivule.pdfIn PDF document text
    • http://strategie-online.net/catalogue_dynamique/file/daliviserilefega.pdfIn PDF document text
    • http://frigotechreina.com/userfiles/files/rajudirizojopofesukaxix.pdfIn PDF document text
    • https://gpuhub.net/wp-content/plugins/super-forms/uploads/php/files/3tgfecmcpm1u3djjv5c0balgm4/jexadazowijunaxeb.pdfIn PDF document text
    • https://luminex.pl/upload/file/53880086634.pdfIn PDF document text
    • http://around-sicily.net/userfiles/file/zefanewewupaxubewisalunow.pdfIn PDF document text
    • http://novehorizonty.sk/userfiles/file/pivamifawel.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=arioso+bach+piano+pdfPDF 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_off0000e138.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE138 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f94a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF94A 19920 bytes
SHA-256: 8aecaa62f69a6a5d51e9ce6cf8d91f4d62b47c79de9fa517c7898566973d1c52
font_02_sfnt_off00012d2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D2D 10560 bytes
SHA-256: b1d23e593f6bb5e07f872c1a6cd18ad976472811bfe1ef7280fbe7366748783f