Malicious PDF — malware analysis report

Static analysis result for SHA-256 42fc785373a27646…

MALICIOUS

PDF

87.5 KB Created: 2021-09-18 07:02:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 04a2bbb9dc21006b97964e02e52c7407 SHA-1: ce7ee5b6879767f287b69c6c528d9ed0db4cd7cc SHA-256: 42fc785373a2764686762ff099c8ff0995175eba3c66c6c021f656b11673df33
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. It contains numerous links to external websites, many of which are hosted on disposable domains or compromised CMS uploads, suggesting a link farm designed to redirect users to phishing or malware hosting sites. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, further obscuring its true purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://royalgoodviewresort.com/Uploads/file/rubojeramezusadaj.pdf In PDF document text
    • http://aftckwt.com/uploads/file/71607916275.pdfIn PDF document text
    • http://queensparkview.com/image/upload/File/tarorufuf.pdfIn PDF document text
    • http://reanda.com/jingkelun/userfiles/files/20210901080249.pdfIn PDF document text
    • http://888chji.com/userfiles/files/65931356978.pdfIn PDF document text
    • https://e-room.co/userfiles/file/gurefedof.pdfIn PDF document text
    • http://mirai-kankyo.com/userfiles/files/fufumubol.pdfIn PDF document text
    • http://i-p-p-c.com/ckfinder/userfiles/files/83600089044.pdfIn PDF document text
    • https://www.andeanskyline.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139346f99d32---sukosotitixemetatifu.pdfIn PDF document text
    • https://oneremote.ru/wp-content/plugins/super-forms/uploads/php/files/05ebd0a1a23fc5e843fbf978f6142d7b/witugosimopivigad.pdfIn PDF document text
    • https://ceccargiurgiu.ro/userfiles/file/pegeda.pdfIn PDF document text
    • https://balbok.net/admin/ckfinder/userfiles/files/22246621358.pdfIn PDF document text
    • https://sdudyogtechnologies.in/ckfinder/userfiles/files/vavilopasi.pdfIn PDF document text
    • http://majedalkarkhi.com/pics/file/zatulipeladofal.pdfIn PDF document text
    • http://kbchina.de/upload/18891766866.pdfIn PDF document text
    • http://ineke-ott.nl/keramiek-beelden-imagesfile/vubigupesufimimejelekes.pdfIn PDF document text
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613764348710a---tobavuvawagafofuliwe.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/qcuov5t0cs53pnqnmluqomk5v8/59871700793.pdfIn PDF document text
    • http://bukvoznaika.ru/ckfinder/userfiles/files/75263969106.pdfIn PDF document text
    • http://medob.org/SITE/files/editor/file/wimulabixebiw.pdfIn PDF document text
    • http://draftingfloorplan.com/ckfinder/userfiles/files/matefar.pdfIn PDF document text
    • http://chistogood.ru/admin/ckfinder/userfiles/files/92223272548.pdfIn PDF document text
    • http://cuoredicane.it/userfiles/files/73100873129.pdfIn PDF document text
    • https://atlas-consulting.ro/fckeditor/fisiere/file/zozotasovivubotema.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=form+one+lightsaberPDF 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_off0000f036.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF036 10672 bytes
SHA-256: ca751ea50b48eb44ab3ec500790f951a40cf2989c5b65c93e32d37ad757b29bc
font_01_sfnt_off0001086e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1086E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012080.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12080 18460 bytes
SHA-256: 95ec0c68c47c60868ba0197be031d7e2b9ec86a4b5745f2ee47f0230334acb35