Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb09c51307dfcc05…

MALICIOUS

PDF

68.4 KB Created: 2021-09-24 17:12:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 18baa4a4144c1302f18846a3ce128378 SHA-1: 67937c404c2718e0ea008c2c1bc00e093335bd2b SHA-256: cb09c51307dfcc0544783e4b0a1575d7257a28af5a60436d99b54dd2d19efe8c
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF exhibits characteristics of a phishing lure, using an image-based design with embedded clickable links. Heuristics indicate it's a link farm pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to distribute malicious content or redirect users to phishing sites. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 68 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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://wastran.ru/uplcv?utm_term=blocky+cars+online+mod+apk
    • https://cashofferoregon.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613100d21a7bf---60827196632.pdf
    • https://sikdercollegeofpharmacy.com/scp/ckfinder/uploads/userfiles/files/ridosujinetuzepofakijizo.pdf
    • http://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/16144552f019db---49540833355.pdf
    • http://cambridgekapurthala.com/damana/userfiles/file/fazuzuzudupoluzakamofos.pdf
    • https://espritgt.com/userfiles/file/rudakogomodizamafuwojug.pdf
    • https://www.jaegeraviation.com/ckfinder/userfiles/files/53745229943.pdf
    • https://minlinart.com/archive/upload/files/divuxezovi.pdf
    • https://vannordenvastgoed.nl/userfiles/file/nirufaxenolijiwiv.pdf
    • https://northwestconvention.cz/data/files/9814447357.pdf
    • http://d2dgroup.net/upload/files/buruvafixidojuzopiwek.pdf
    • http://yuqiaohome.com/uploads/files/202109020647454801.pdf
    • http://murasakijr.com/uploads/files/5167479049.pdf
    • http://dlzj.net/upload/files/20210901165902944105.pdf
    • https://resonanceacteurs.nl/userfiles/file/balitodogudiko.pdf
    • http://kidsjeodo.com/images/files/21146008206.pdf
    • http://www.gesas.it/media/mailinglist/file/92563737486.pdf
    • http://culbertsonlawyer.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/sudusapoku.pdf
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/161327035de646---punupojixafuxowosesadupa.pdf
    • https://www.vigo.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1613df61e24d02---47988875318.pdf
    • http://ziepniekkalns.lv/wp-content/plugins/formcraft/file-upload/server/content/files/16136439817b55---40419828427.pdf
    • http://opusincertum.it/userfiles/files/72488442802.pdf
    • http://www.cenlajobinator.com/siteuploads/editorimg/file/9588176758.pdf
    • http://meetburgerusa.com/uploads/files/veguwot.pdf
    • http://www.kizkulesikizogrenciyurdu.com/public/ckfinderuploads/files/3240140616.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_off0000b00d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB00D 16792 bytes
font_01_sfnt_off0000c81f.bin
053bed341a4979d480b3e977cf9ccfca2e615f2595ca04c7afed766c40e80c8a
pdf-font-stream PDF embedded font (sfnt) at offset 0xC81F 14092 bytes
font_02_sfnt_off0000eb6c.bin
08c27804833a18eff18a2e3e56b4cb440a4b95155d1f3b36bac1abd576be799d
pdf-font-stream PDF embedded font (sfnt) at offset 0xEB6C 10836 bytes