Malicious PDF — malware analysis report

Static analysis result for SHA-256 90c97f75f73dc0e9…

MALICIOUS

PDF

74.9 KB Created: 2021-09-08 09:56:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 652dc75941227e745a4fbf9a0dccdc2d SHA-1: d94ffcf2a94c23ba376bd4eff365f33da74d3983 SHA-256: 90c97f75f73dc0e91f370d50dd3563982dbeb604601ef5a7c25a1481e8f99ace
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many pointing to compromised WordPress sites, indicating it functions as a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to redirect users to phishing pages or download further malware. No scripts were extracted, but the structure and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/16132e0b45b35e---subopas.pdf In PDF document text
    • http://hzzxtl.com/UploadFile/file/20210823151837012.pdfIn PDF document text
    • http://bigband-ulm.de/userfiles/files/20362266168.pdfIn PDF document text
    • http://challendor.com/fckeditor/upload/file/vagivedaxagonoxofebakopi.pdfIn PDF document text
    • http://remaining-mc.de/userfiles/file/kuwirutafozuvijimusomaxi.pdfIn PDF document text
    • https://puntoagricoltura.it/file/11016028248.pdfIn PDF document text
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba5aa08fb91---23611156240.pdfIn PDF document text
    • http://americanewbie.com/userfiles/file/39280352691.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/708b484455791292fc622d57eb2440ab/senebaxituzolirumop.pdfIn PDF document text
    • https://kimansion.com/uploads/file/71793365746.pdfIn PDF document text
    • https://jetzterstrecht.hamburg/wp-content/plugins/super-forms/uploads/php/files/pvub0hjgdf27letb78vr96dk81/98740526141.pdfIn PDF document text
    • http://sipzip.com/userfiles/file/jufoxunedivi.pdfIn PDF document text
    • http://dianacb.cz/userfiles/file/xojolokewigeduduk.pdfIn PDF document text
    • http://c2mag.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ef6b85d183---pinogegelukegu.pdfIn PDF document text
    • https://aletihad-group.com/userfiles/files/jurazipekifa.pdfIn PDF document text
    • http://kfnmdg.com/upfolder/e/files/20210610080622.pdfIn PDF document text
    • http://ferrocom-spb.ru/userfiles/files/genenikivuliwami.pdfIn PDF document text
    • http://seamcc.com/UserFiles/files/26983837630.pdfIn PDF document text
    • http://polesprogettazioni.com/userfiles/files/98665274053.pdfIn PDF document text
    • http://staging.impactredevelopment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c682e2bb6d---senexod.pdfIn PDF document text
    • https://uleiuri.ro/userfiles/file/zezatuxoxere.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=women%27s+lacrosse+rules+2018+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_off0000c20d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC20D 11220 bytes
SHA-256: b4090cf8f20be39f0a0ebdfbe6a812c9a3db9af6b18bd0986fc10b9cd7c755d2
font_01_sfnt_off0000dc77.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC77 16536 bytes
SHA-256: 148e22614183461bbfd10393145e16f6c0d4a59b66dfe60e3171712abf889c5a
font_02_sfnt_off00010654.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10654 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1