Malicious PDF — malware analysis report

Static analysis result for SHA-256 681f7517a20066c3…

MALICIOUS

PDF

92.0 KB Created: 2021-09-02 05:50:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 980d49bd1413533dd3483dd7d1b5107e SHA-1: 4901d4012d6b7804245d88b41a89713f3c5b2aef SHA-256: 681f7517a20066c318760c0ba2b593566058be26d55a1637d8ba949c97d28f80
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to numerous compromised websites, many of which are WordPress uploads. These links are likely used to distribute phishing content or further malware payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9876

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://tttinox.com/upload/userfiles/files/jinunikedodu.pdf In PDF document text
    • https://bistro-8.com/wp-content/plugins/super-forms/uploads/php/files/e22d3b78a0216bcfc17ff4592e3bc70f/61127256110.pdfIn PDF document text
    • https://www.inkfactory.pk/wp-content/plugins/formcraft/file-upload/server/content/files/160b75253c1c46---5290939279.pdfIn PDF document text
    • http://erbilsunhotel.com/wp-content/plugins/super-forms/uploads/php/files/rbkcn4433r719t7ana530o5m01/59746586864.pdfIn PDF document text
    • http://4x4autok.hu/userfiles/files/judalopevafin.pdfIn PDF document text
    • http://ilovehikari.com/uploads/files/jorefosulago.pdfIn PDF document text
    • https://hospvetcentral.pt/site/upload/file/97494833860.pdfIn PDF document text
    • https://gastriklandsbf.se/UserFiles/files/88451546945.pdfIn PDF document text
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16077b761426f2---mokulutewajitelunutoser.pdfIn PDF document text
    • http://nsmpublicschool.org/slbdavbatala/userfiles/file/jorofuzasofurowabiwam.pdfIn PDF document text
    • http://didula.com/img/file/78452815729.pdfIn PDF document text
    • http://gsoutreach.net/clients/e/ea/ea4f28bd0b090870cbed8536b6d1d406/File/62618347400.pdfIn PDF document text
    • https://ateneoarbonaida.com/wp-content/plugins/formcraft/file-upload/server/content/files/16111e3fa6bde6---webizepuwamomewed.pdfIn PDF document text
    • https://www.visitrwanda.com/wp-content/plugins/super-forms/uploads/php/files/c18db6e034f56c494209014012462573/sizunoxejesiroruji.pdfIn PDF document text
    • http://luyenthidhcanhsat.com/Images_upload/files/jedenuzumu.pdfIn PDF document text
    • https://sg-design.top/wp-content/plugins/super-forms/uploads/php/files/97826a32c6b98802dcbab50561ab4bdf/27695758002.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/lububorifenidilifemajef.pdfIn PDF document text
    • http://maytinhtuyenquang.com/home/maytinhtuy/domains/maytinhtuyenquang.com/public_html/images/file/85551425798.pdfIn PDF document text
    • http://gobelsprofil.com/upload/files/470990243.pdfIn PDF document text
    • http://pcwenhua.com/uploadimg/file/16283438981386904119.pdfIn PDF document text
    • https://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa8be25644c---mofakiwixazesefelumu.pdfIn PDF document text
    • https://riwg.in/userfiles/file/89414700303.pdfIn PDF document text
    • http://phillipwhiting.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082cab022e7e---fajudemovakek.pdfIn PDF document text
    • https://www.indee-r.fr/wp-content/plugins/super-forms/uploads/php/files/6f93334559cbf469c6587106c5ea4dd5/29523497492.pdfIn PDF document text
    • https://kvartira-zalog.ru/wp-content/plugins/super-forms/uploads/php/files/b7107ea4d34d57f224112d89150a5669/vufesepegafixizivezufe.pdfIn PDF document text
    • http://asesoriagarpe.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ada16ff2ae5---68849545090.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=s+varies+directly+as+tPDF 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_off0000ffe9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFE9 19528 bytes
SHA-256: 05817b2b57fb70335972a75a94a8cd4163a78f2884c0c4485f3b185a0f7f1323
font_01_sfnt_off00013260.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13260 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00014a77.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14A77 10396 bytes
SHA-256: 30b2dfb163c9e4a7d5bb4f94919b136ac62f67ad8c5daa506ebe75e72758e6fe