Malicious PDF — malware analysis report

Static analysis result for SHA-256 c91f30ea8bd6094e…

MALICIOUS

PDF

70.1 KB Created: 2021-09-25 00:26:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: e968cbd729924d4e8dbd279937c6b990 SHA-1: 998f4cc353d6243d08228b5162944c7cca62fe92 SHA-256: c91f30ea8bd6094ef8c6de9ed6ca28fdc153cf9d671abbc6a4a68a30f1e88691
156 Risk Score

Malware Insights

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

The file is a PDF identified as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs, many of which point to compromised CMS upload directories or are structured as link farms on disposable hosting, suggesting an attempt to lure users to external sites. The presence of these links indicates a likely phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://oniceh.ru/uplcv?utm_term=minecraft+cool+base+ideas PDF link annotation
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/b72b2d4326fd5a29fb612d7e1e9c69b3/32642992591.pdfIn PDF document text
    • https://peintures-descours.fr/fichier/files/laloxasof.pdfIn PDF document text
    • http://dungcucaytrong.com/images/files/60462382510.pdfIn PDF document text
    • http://metrocars.london/survey/userfiles/files/22545846536.pdfIn PDF document text
    • https://realxenon.ru/uploads/files/tulutitisinavofidopujasen.pdfIn PDF document text
    • http://shippingengineering.com/files/ckeditorothers/zikuwuritasawi.pdfIn PDF document text
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/1614af0786f3a0---66917455794.pdfIn PDF document text
    • http://vanguardhungary.hu/userfiles/file/seropedejope.pdfIn PDF document text
    • http://kssi.ir/public/userfiles/file/jinewuzupajudaweg.pdfIn PDF document text
    • http://drairtools.com/ckfinder/userfiles/files/pesurugedigofozodujotowig.pdfIn PDF document text
    • http://napiarsaigh.com/images/20520505754.pdfIn PDF document text
    • http://mackielaw.net/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/25454004428.pdfIn PDF document text
    • http://quangphong.vn/uploads/image/files/81500784088.pdfIn PDF document text
    • https://sydneystudytour.com/accounting/userfiles/file/27222610090.pdfIn PDF document text
    • http://www.ponderosafestival.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614582191a9c4---xawanaduboveloxidunalofaj.pdfIn PDF document text
    • http://yangs-ns.com/ckfinder/userfiles/files/20210917153744.pdfIn PDF document text
    • http://fapannimario.it/userfiles/files/67099025910.pdfIn PDF document text
    • https://martan.es/cenavarra_userfiles/files/53236733963.pdfIn PDF document text
    • https://highendteen.com/userfiles/files/46212941541.pdfIn PDF document text
    • https://mavismanagement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ef94cbf6a0---gojifagataziv.pdfIn PDF document text
    • http://www.grupoaccs.net/ckfinder/userfiles/files/rolavebiwuru.pdfIn PDF document text
    • https://koncnc.com/genelresimler/file/negawuparutagabedalejolid.pdfIn PDF document text
    • http://planao.com/ckfinder/userfiles/files/73775568164.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_off0000b094.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB094 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c8a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8A6 16696 bytes
SHA-256: d2fb494e5e3948df97ac0184fa2e312e772d040d6f9920ff0c16779df8b99013
font_02_sfnt_off0000f321.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF321 10604 bytes
SHA-256: 68f71b43bdddb3e2a440d737c279683999f17dc52c8cde332227d01ec4d02744