Malicious PDF — malware analysis report

Static analysis result for SHA-256 11897f91f3c331a0…

MALICIOUS

PDF

80.1 KB Created: 2021-09-02 18:17:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: ff9c3fae6df41cfee2782f31eddaf53c SHA-1: 455af0618dcac0ca1bfc8567ba1b00f2af591f0d SHA-256: 11897f91f3c331a040759b37ecfc76252d78cc40dce5bb963d75a668a3660422
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised WordPress sites, suggesting a link farm or phishing lure. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a phishing or malware distribution campaign, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://crewmak.ru/uplcv?utm_term=concept+of+national+income+in+economics+pdf PDF link annotation
    • http://www.akutrans.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c2d731a1d5---vuxujezus.pdfIn PDF document text
    • http://darienhigh70.com/clients/878490/File/zogezonazudona.pdfIn PDF document text
    • http://postelezmasivu-brno.com/ckfinder/userfiles/files/62896011473.pdfIn PDF document text
    • https://gencerenerji.com/resimler/files/visimowemitapogo.pdfIn PDF document text
    • http://adamlegal.com/userfiles/file/mudejefazixasodovafeliba.pdfIn PDF document text
    • http://ingegnasrl.com/userfiles/files/rusogisagewuguxewetazuza.pdfIn PDF document text
    • http://marinapogon.pl/upload/file/ginosinazima.pdfIn PDF document text
    • https://n95america.com/wp-content/plugins/super-forms/uploads/php/files/5ff541e4d826e2d50be6c9b004511b55/81179709233.pdfIn PDF document text
    • http://mea-travel.pl/userfiles/file/47457770048.pdfIn PDF document text
    • https://sipare.com.ar/wp-content/plugins/super-forms/uploads/php/files/ift1tss5vg73nl42bgf26pvaon/zekiritesiwonavos.pdfIn PDF document text
    • http://omg.su/upload/File/dejuzix.pdfIn PDF document text
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098a4b0eacaf---63143445750.pdfIn PDF document text
    • https://dacinsara.ro/fckfiles/file/3049519727.pdfIn PDF document text
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a12318778d---92757434133.pdfIn PDF document text
    • https://bartonsteel.com/tony/barton/ckfinder/userfiles/files/11428153019.pdfIn PDF document text
    • http://icsbc.ru/fuploader//file/91357018526.pdfIn PDF document text
    • https://toyotaautobody.com/ckfinder/userfiles/files/pefokimanafuseludaximazef.pdfIn PDF document text
    • http://renovator.cz/files/file/1532812598.pdfIn PDF document text
    • http://4seasonstours.in/userfiles/file/lejarubitukajulosukofin.pdfIn PDF document text
    • http://www.ausafrica.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160caa31e7327b---26577298419.pdfIn PDF document text
    • https://spectrumohio.com/wp-content/plugins/super-forms/uploads/php/files/795c077dbdb390025165ae6d06463965/tuzokojuvumimasapovu.pdfIn PDF document text
    • 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_off0000d575.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD575 10712 bytes
SHA-256: f591522228196b571a5ea0822e133829a24ce6137a9134a110fb1403f7b9b12c
font_01_sfnt_off0000ee09.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE09 17240 bytes
SHA-256: 157738b4c9a964d236e154e9faddecf8ad96f1bd183361f2b208f27df0563b4f
font_02_sfnt_off00011abb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11ABB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1