Malicious PDF — malware analysis report

Static analysis result for SHA-256 d1ac28fc31ca0bb6…

MALICIOUS

PDF

83.9 KB Created: 2021-09-14 07:33:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: c2e7ebb788bf38253bff24f3586e48ec SHA-1: 27ff433bc64746c9be28c86cd5265c5fc1cd87a8 SHA-256: d1ac28fc31ca0bb6f8d42774aca197d2416b99fd93d02352661bb50edf23d012
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains a large number of embedded URLs, many pointing to disposable hosting, indicating a link farm designed to redirect users to malicious sites. The 'wkhtmltopdf' authoring application suggests it may have been generated programmatically for this purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://smidgel.ru/uplcv?utm_term=yunos+android+apps PDF link annotation
    • http://www.recetasyconsejos.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135c983ef22c---sibupulilixa.pdfIn PDF document text
    • http://xn--jt2b56wn0ap2a.com/upload/file/202109060108559426.pdfIn PDF document text
    • http://nfc.soo.jp/file/jakijuwugojigamim.pdfIn PDF document text
    • http://chemtron-vostok.ru/media/file/3699700261.pdfIn PDF document text
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613ff16b5aa08---66403917476.pdfIn PDF document text
    • http://issaproject.com/app/views/panel/ckfinder/userfiles/files/14787748333.pdfIn PDF document text
    • http://moderncarrent.com/user_img/files/62146938951.pdfIn PDF document text
    • http://tai-group.com/upload/files/94494575663.pdfIn PDF document text
    • http://mosvag.ru/img/lib/file/luditalepexafexofu.pdfIn PDF document text
    • http://foxgraphics.paulsfashion.in/files/sodor.pdfIn PDF document text
    • http://riversedgefm.com/files/file/dumegavivoxamiluw.pdfIn PDF document text
    • http://xn----0tbbbfo0f.xn--p1ai/userfiles/file/wanidepoz.pdfIn PDF document text
    • http://master-sign.ru/ckfinder/userfiles/files/34434233126.pdfIn PDF document text
    • http://enjoyisagenix.com/ckfinder/userfiles/files/82526834355.pdfIn PDF document text
    • http://kkagro.com/media/images/upload/file/63682027334.pdfIn PDF document text
    • http://odnoklassniki-files.ru/images/uploads/files/vumevogonaletafimuj.pdfIn PDF document text
    • https://meesens.be/KrMee/Tekstverwerker/busidodabit.pdfIn PDF document text
    • https://weborder.cloud/userfiles/file///32631364520.pdfIn PDF document text
    • http://aqs-group.it/userfiles/files/napug.pdfIn PDF document text
    • http://traiteurluc.com/userfiles/file/difuzorofelawaluvi.pdfIn PDF document text
    • https://lecachet.fr/docs/files/vifijepuzezetinubojizitiz.pdfIn PDF document text
    • http://pepinieres-soupe.com/userfiles/file/bebefafajurarozelor.pdfIn PDF document text
    • https://tselectromechanical.com/uploads/CKfiles/files/zaxaripotezulekanumokasap.pdfIn PDF document text
    • http://stuarteisbrucklaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/rebipororu.pdfIn PDF document text
    • http://elezioni2014.gds.it/userfiles/file/padiwepiwonufigemenu.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_off0000d95a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD95A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f16c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF16C 21348 bytes
SHA-256: e1c176bf4e7b9aeee60a426006c0b82ffca134abdd3733cba58546328435f434
font_02_sfnt_off000129f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x129F5 10192 bytes
SHA-256: a186853444bc6eee535a496bc84e7f46319c6f5fea5ee0ddebf6113f6ce8bd8f