Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8dd86c6bdabc688…

MALICIOUS

PDF

68.9 KB Created: 2021-09-29 08:56:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 430bee306453f555d7895a7d6b853f04 SHA-1: 48b4ff079f1a8d8b2eae8e891051acdbbdb878a8 SHA-256: a8dd86c6bdabc688011754b72d05b25628d4eba9bf327ca78e296af71b3aff9c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external URLs, some hosted on compromised WordPress sites. The embedded URLs and the overall structure suggest an attempt to trick users into visiting malicious sites, likely for credential harvesting or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://catamma.ru/uplcv?utm_term=no+man%27s+sky+android
    • http://illinoislivestock.org/userfiles/file/77361641476.pdf
    • http://kondicionery-lubertsy.ru/upload_picture/file/87394946313.pdf
    • https://hkbca.org/UploadFiles/file/20210907222109116.pdf
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/gjut8k0b2uqear1v4m6cf0gdhn/fujogezabuta.pdf
    • http://webbyshoe.com/fckeditor/userfiles/file/98410183491.pdf
    • https://loyallcanada.net/editor_files/file/74320561995.pdf
    • http://danies.ru/ckfinder/userfiles/files/ganipofenalada.pdf
    • http://inistor.com/ufiles/files/95528633049.pdf
    • http://studiofranzoni.eu/userfiles/files/36990215454.pdf
    • http://pinxedien.net/upload/files/28262042648.pdf
    • http://mikllc.mn/uploads/files/57674259648.pdf
    • https://shaksheer.com/app/webroot/upload/files/bukokewovizedavarit.pdf
    • http://jinruily.com/UploadFile/file/20210902102842625.pdf
    • http://bluebossa.pl/files/file/2194277872.pdf
    • https://daks-96.com/f/uploads/files/difagonulenava.pdf
    • https://horkolas-gatlas.hu/ufiles/file/sapaduto.pdf
    • http://namthangbasaltstone.com/uploads/image/files/towudajetu.pdf
    • https://huangs.tw/uploads/files/202109162304366693.pdf
    • http://eskuvoiiranytu.hu/blog/file/45623465987.pdf
    • https://www.popcaffe.it/wp-content/plugins/super-forms/uploads/php/files/e5504cbc326580b3cfe2b0e14d138e9a/bezuxasoj.pdf
    • http://moveisgarciadigital.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161481bd39b46e---gamubapuxafaxokaxolosesu.pdf
    • http://identik.hu/editor_up/kizinefikete.pdf
    • http://giteduguedesboires.com/userfiles/file/68823528255.pdf
    • https://baatco.com/ckfinder/userfiles/files/nuvirozeditifeluxilowi.pdf
    • https://bxthirteen.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/00e42def6cb2f441a6a293760858a2b6/dexavukivawogowag.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b122.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB122 16792 bytes
font_01_sfnt_off0000c934.bin
9bbc64b2cac7ce771a796144aba56e9c65e551b77d58b92a8828b31a5ee0613d
pdf-font-stream PDF embedded font (sfnt) at offset 0xC934 15004 bytes
font_02_sfnt_off0000ef0c.bin
d690ac5fb48ac1f1147a1564a13ed650199261d47ef2c03ce47d63a6a3d28e44
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF0C 10352 bytes