Malicious PDF — malware analysis report

Static analysis result for SHA-256 e1540e5d999a80ed…

MALICIOUS

PDF

68.1 KB Created: 2021-10-01 13:13:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-03
MD5: 81cf33cdd4afdb469d824068ee3c3316 SHA-1: 811957f0ffbfd5534082e5990404fc5a2461a18a SHA-256: e1540e5d999a80edf49e90b0516f1a47ba4877103d9cbdb274da557b06a70215
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many pointing to compromised WordPress sites and disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious document delivery mechanisms.

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 https://crewmak.ru/uplcv?utm_term=versi+android+6 PDF link annotation
    • https://safetypadlocks.eu/eurostyl/photos/file/kadepanuwuvonuj.pdfIn PDF document text
    • https://stcatherine.ac.ug/wp-content/plugins/formcraft/file-upload/server/content/files/1613adf1461ef2---xivijojajinikikimag.pdfIn PDF document text
    • https://afmiletisim.com/resimler/files/79544034324.pdfIn PDF document text
    • https://zazilha.com.mx/wp-content/plugins/super-forms/uploads/php/files/c22d370317acbbdb749d9a4556ef104c/firulavegejerudobepalovo.pdfIn PDF document text
    • http://utpcomp.ru/uploads/files/betibegarukepotegaxubod.pdfIn PDF document text
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615681aec4d9e---76932280280.pdfIn PDF document text
    • https://xosobacninh.vn/webroot/img/files/97568089479.pdfIn PDF document text
    • https://fetogram.ir/images/upload/files/43265822502.pdfIn PDF document text
    • https://baobiachau.com/luutru/files/23025155497.pdfIn PDF document text
    • http://bangtaisay.com/uploads/userfiles/file/junojuwikesuva.pdfIn PDF document text
    • http://annabarons.lv/files/files/93248295148.pdfIn PDF document text
    • http://stigstudiotecnico.it/userfiles/files/86992383654.pdfIn PDF document text
    • https://k-barrierfree.com/FileData/ckfinder/files/20210929_669697EC7A70FE71.pdfIn PDF document text
    • http://alfavs.eu/userfiles/file/tozezolinibo.pdfIn PDF document text
    • http://lev-steklo.ru/userfiles/file/47604244473.pdfIn PDF document text
    • https://krantiservice.com/ckfinder/userfiles/files/78947727509.pdfIn PDF document text
    • http://biomehl.com/images/content/files/82473314759.pdfIn PDF document text
    • http://hide-bo.com/img/tmp/file/mopidafa.pdfIn PDF document text
    • https://inprovitcolombia.com/ckfinder/userfiles/files/kibixezufawuboxogawir.pdfIn PDF document text
    • http://garmaclima.com/uploads/ckfinder/files/zukuvivosevuzuz.pdfIn PDF document text
    • http://printific.com/images/contentimages/files/taverutaxinofobata.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_off0000ac9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAC9B 15796 bytes
SHA-256: 249d254a71ddb78a9cfab7797d039171f7f6683cb55336b04d03a135bb7a6cf2
font_01_sfnt_off0000d468.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD468 10236 bytes
SHA-256: 5d02109a015365976bab605d0eb1ba78163ecc12afc873b4b8a8e89acc040809
font_02_sfnt_off0000eb80.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB80 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1