Malicious PDF — malware analysis report

Static analysis result for SHA-256 21288a793ee4a23e…

MALICIOUS

PDF

84.9 KB Created: 2021-09-16 20:47:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: b7826f352b886b843577f5c19d5ac240 SHA-1: 1f5597e19ff73341c78c2e1987989c3831ef81bf SHA-256: 21288a793ee4a23e397ad67201f25bb0bea2d09a52ac1f729aacc2d31e3e5af5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which are part of link farms hosted on potentially compromised or disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery. The presence of external URI heuristics and link farm indicators suggests the primary goal is to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

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://inwebjor.ru/uplcv?utm_term=poco+x2+latest+update+download PDF link annotation
    • https://markiza-trade.ru/admin/ckfinder/userfiles/files/56783881327.pdfIn PDF document text
    • http://adhdesign.de/userContent/files/20210911080053-79001521420.pdfIn PDF document text
    • http://baheth24cars.com/ckfinder/userfiles/files/nijibapomotu.pdfIn PDF document text
    • http://pradakshinam.com/fck_uploads/file/4105229352.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/e0be24c4dc881726d738dc58a056def9/35557434760.pdfIn PDF document text
    • https://vidaleve.net/ckfinder/userfiles/files/konobutimipavedafagegudad.pdfIn PDF document text
    • http://studiofranzoni.eu/userfiles/files/8211838176.pdfIn PDF document text
    • https://doellefjelde-mussemarked.dk/images/newsmail/file/xegepulavozamil.pdfIn PDF document text
    • http://mfcwestenkwartier.nl/beta/userfiles/file/ziwuxasekud.pdfIn PDF document text
    • http://vtdsbinhthuan.vn/public/uploads/userfiles/file/97853077503.pdfIn PDF document text
    • https://bibliothequedesarts.ch/ckfinder/userfiles/files/xuwanodiwavud.pdfIn PDF document text
    • http://contactfm.be/userfiles/files/83216760306.pdfIn PDF document text
    • https://maisonforville.be/documents/file/69362259315.pdfIn PDF document text
    • https://spvi.cn/filespath/files/20210909212658.pdfIn PDF document text
    • https://bi-kiesabbau.de/cmsimple/images/file/fifovizi.pdfIn PDF document text
    • http://marisqueandopremios.com/campannas/file/nimuvetemideposozoxo.pdfIn PDF document text
    • http://artpolinakuzina.ru/pict/file/woladud.pdfIn PDF document text
    • https://www.traveltimevipp.com/wp-content/plugins/super-forms/uploads/php/files/43cfdf813e69bd1b4c35999bf70b95b6/17929174901.pdfIn PDF document text
    • https://ipekyolumedya.com/resim_galeri/file/44122224858.pdfIn PDF document text
    • https://takipbizde.com/calisma2/files/uploads/65580882626.pdfIn PDF document text
    • https://asiatravel.kg/wp-content/plugins/super-forms/uploads/php/files/2aa91fbb888cfdf07fc8f3a097c90aa7/tisolabilekinepivuxufi.pdfIn PDF document text
    • https://parvazyab.com/basefile/api203/files/momorikagoneme.pdfIn PDF document text
    • https://ceadersvalet.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613114196c022---88779523618.pdfIn PDF document text
    • https://shen-su.eu/gfx/userfiles/files/goluzuwofebe.pdfIn PDF document text
    • http://nenorm.com/files/files/88010613423.pdfIn PDF document text
    • http://polyacer-ecp.com/userfiles/files/20210905_085608.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_off0000e7ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7CE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ffe0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFE0 17500 bytes
SHA-256: 96360be2c1244ff9d2fa54bd2d6288be58744f6a14d082db42b0c771de133c6e
font_02_sfnt_off00012cf3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12CF3 10724 bytes
SHA-256: de42bb86a838180f3c1af428eb58f2eb74713ef7640b59aefd76df355c0fc405