Malicious PDF — malware analysis report

Static analysis result for SHA-256 88c28ff172599a46…

MALICIOUS

PDF

80.6 KB Created: 2021-09-08 05:08:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 029c302b9079a7418c0b748a3abdb309 SHA-1: f192599b3a9c2403ebc64bd82ccfbea6b07ecaa7 SHA-256: 88c28ff172599a46fd63d995811aa0ad1bf2e51e02b549c8d12a477b4aaa97bc
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to various domains, likely to download further payloads. The 'SE_INVOICE_LURE' heuristic suggests the document's content is designed to trick users into clicking these links, aligning with a phishing attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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 https://smidgel.ru/uplcv?utm_term=npo+registration+form+pdf PDF link annotation
    • https://allegypttours.net/userfiles/files/nexilomi.pdfIn PDF document text
    • https://bio86.net/fichiers/92872283859.pdfIn PDF document text
    • https://kachhiproperties.com/wp-content/plugins/super-forms/uploads/php/files/8nc2rvtckood8bfc9pjm72n971/vexikepifamezap.pdfIn PDF document text
    • http://xlpe.net/Images_upload/files/16238236968.pdfIn PDF document text
    • https://lensprovn.com/ckfinder/userfiles/files/56341410052.pdfIn PDF document text
    • http://teusz.pl/UserFiles/file/30180941866.pdfIn PDF document text
    • http://www.kickcommerce.com/userfiles/file/geroxojuguw.pdfIn PDF document text
    • https://sygimportaciones.com/wp-content/plugins/super-forms/uploads/php/files/4kc58e41ss3pv4dujghtvi43rf/xavubepibaki.pdfIn PDF document text
    • http://btc-ltd.com/upload/file/nujuwutelo.pdfIn PDF document text
    • http://iacsglobal.iacsinfo.org/content/uploads/files/82027557784.pdfIn PDF document text
    • http://privateeducation.sg/verzsape/demo/upload/admin/files/19802609177.pdfIn PDF document text
    • https://www.mnspineandsport.com/wp-content/plugins/super-forms/uploads/php/files/70af6343a53d617b7cd05c746bc1a9a7/26878473838.pdfIn PDF document text
    • http://honyi.tw/ckfinder/userfiles/file/30712166491.pdfIn PDF document text
    • http://studiotecniconuti.it/userfiles/files/lifotomododogoxonazodu.pdfIn PDF document text
    • https://infravoip.com/wp-content/plugins/super-forms/uploads/php/files/cfa5c1ebd76326ce95fb8e9ce470b1b7/vowunexerofazuvejeferofav.pdfIn PDF document text
    • http://vyveva.eu/UserFiles/File/46294454214.pdfIn PDF document text
    • https://militarynetwork.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16089bcce4adaa---85499514894.pdfIn PDF document text
    • http://abovomedia.hu/_user/file/wonikosolesix.pdfIn PDF document text
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/309b3ad08344996199f11d8341edf457/94746284358.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_off0000d74e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD74E 10772 bytes
SHA-256: 6c7b340472b26e3ffe6f6214529d72cf771a8f878c0c4a9f32e1efb0869568af
font_01_sfnt_off0000efe7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFE7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000107f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107F9 17328 bytes
SHA-256: 0a24517fbe3932f27ecc7b186c75005ce1791cac1257670b553b27bb8442cae1