Malicious PDF — malware analysis report

Static analysis result for SHA-256 92db3439148ba327…

MALICIOUS

PDF

83.1 KB Created: 2021-08-18 10:12:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-02
MD5: 5f61d8bbe534df6cbdcf585e232a83ef SHA-1: 4e6728abdef68565152472e4f4672a16239ec002 SHA-256: 92db3439148ba327c008605c395865d19dc41d234e89a8e586f0be054bf2e9c4
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. It uses an invoice-themed lure. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9925

Heuristics 7

  • 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.
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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://accessiblevehicleservices.com/userfiles/file/93777798840.pdf In PDF document text
    • https://www.brunosistemi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8f46f0d016---73606052075.pdfIn PDF document text
    • https://www.ptlittleflower.org/wp-content/plugins/super-forms/uploads/php/files/uca7rup1542hj3qga22nha4se7/lofik.pdfIn PDF document text
    • http://baovephuongtroi.com/vietkiendo/upload/file/fozasogeguvineb.pdfIn PDF document text
    • http://asesoriagarpe.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f97883bd5ee---vedubirurimofamituxolipe.pdfIn PDF document text
    • https://semut73.com/contents//files/wudotitoxidewunexodiro.pdfIn PDF document text
    • https://leunamgroup.com/wp-content/plugins/super-forms/uploads/php/files/c7ce6938b352a4a03f066c77052cefd4/xesezepoxanezuzozo.pdfIn PDF document text
    • https://ijacr.net/assets_admin/ckfinder/core/connector/php/uploads/files/wonovajupibetoraxowoxotab.pdfIn PDF document text
    • http://greaterdeliveranceministries1.com/clients/61527/File/ralaw.pdfIn PDF document text
    • http://nprofit.hk/userfiles/xuwovujowusikaguwus.pdfIn PDF document text
    • http://jointrilogy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608da4a1da1f4---3249170298.pdfIn PDF document text
    • https://www.a2zmedical.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607cecb34574d---60297140826.pdfIn PDF document text
    • http://flywings.sk/UserFiles/file/18862187100.pdfIn PDF document text
    • https://arerp.kr/data/file///35386473478.pdfIn PDF document text
    • https://howardsteeves.com/wp-content/plugins/super-forms/uploads/php/files/4100a99150ef316bffac47b824318b75/zavegoxe.pdfIn PDF document text
    • http://otevrel.eu/ckfinder/userfiles/files/bujesonopad.pdfIn PDF document text
    • http://aiswaryamatrimonials.com/fck_uploads/file/xobavuwifejiwimikube.pdfIn PDF document text
    • https://www.dgaspcsm.ro/ckfinder/userfiles/files/motelejamuxolegubiben.pdfIn PDF document text
    • https://www.vigo.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16095e0704e84c---xikiperedabazefaririx.pdfIn PDF document text
    • http://sistersaviopublicschool.com/userfiles/file/jalumofovaxopomirolen.pdfIn PDF document text
    • http://blessedfamilycovenant.org/clients/c/cb/cb727bc273eb4203dc66fb73741ae5ae/File/vitof.pdfIn PDF document text
    • https://aalatour.com/basefile/b2caalatourcom/files/75373819505.pdfIn PDF document text
    • https://baxsporthorses.com/userfiles/file/1926063758.pdfIn PDF document text
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/16091d11d854eb---zelekububakogodunabuxa.pdfIn PDF document text
    • http://www.homefacelifters.com/wp-content/plugins/super-forms/uploads/php/files/bf2c66d84ec40c9f17f1054576e08d18/wakobigavojato.pdfIn PDF document text
    • http://begemot-rus.com/uploadfiles/file/2021070413181973499.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=how+to+calculate+net+due+date+in+excelPDF 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_off0000e19c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE19C 10372 bytes
SHA-256: 0513ea403c9cd646d38ed37593f4f58e616443975b96ffa1897247a2ecdc338c
font_01_sfnt_off0000f925.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF925 16988 bytes
SHA-256: 2f45142cb19e0978899c4a02addcb699f71633e46b6e8ade16d4c99e9f2aa52d
font_02_sfnt_off000125a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125A6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1