Malicious PDF — malware analysis report

Static analysis result for SHA-256 6e91e7c57462b869…

MALICIOUS

PDF

78.1 KB Created: 2021-09-15 15:13:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5092ba32b825b044169675c9d84ad2d6 SHA-1: aed15caa0271589aed37b2634827dd695abb6417 SHA-256: 6e91e7c57462b869449e7301e14bb94beabf56e3d24ad2267c7c47f98c51637b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample was flagged by a machine learning classifier and ClamAV as malicious. It contains numerous external links, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users. The presence of these links and the PDF's structure indicate it's likely a lure for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

Heuristics 6

  • 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.
  • 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 http://artc-polymers.com/upload/images/files/gisavomataporejiber.pdf
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/0nmb5g3fg3dufv496rrps76iok/49081457602.pdf
    • https://tahuacoop.com/cms_gpadmin2015/sgi_userfiles/userfiles/files/gatigerokuneduladi.pdf
    • http://oletrans.sk/editor_uploads/files/77632417941.pdf
    • https://rougezenekar.hu/files/file/76100412997.pdf
    • http://maxitelt.no/wp-content/plugins/formcraft/file-upload/server/content/files/1613a4fb7ed2ac---fukuxudowawarituwe.pdf
    • http://thai-apsproducts.com/file_media/file_image/file/godisobefigaj.pdf
    • https://snapstudios.ca/userfiles/file/nizukonebujinurikuniji.pdf
    • http://studiofranzoni.eu/userfiles/files/vumogazofopapuximonudaleb.pdf
    • https://www.sevgiliyevideo.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613790743eebf---dalisopawisiti.pdf
    • http://drxzhang.com/userfiles/file/penakaluwijizudova.pdf
    • https://www.lesson-online.org/wp-content/plugins/super-forms/uploads/php/files/konb5oactov7nu6d8uu82s7fc5/fififevifuraz.pdf
    • https://arnetbilgisayar.com/upload/ckfinder/files/miwanerijenotupak.pdf
    • http://bladensburg.abwingsmd.com/uploads/files/zuramuzenisogoxome.pdf
    • https://hongmao.tw/uploads/files/202109112303201370.pdf
    • https://pfollowers.com/ci/userfiles/files/34928785075.pdf
    • https://www.cosanuesa.com/componentes/editor/ckfinder/userfiles/files/nawiriromudo.pdf
    • http://sungwoneng.com/upfile_editor/2021/files/85529317549.pdf
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613857b39f24e---54877713156.pdf
    • http://nerezove-kuchyne.cz/UserFiles/File/35956609185.pdf
    • https://sergiomauri.com/images/file/95867854371.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=joystick+apk+for+pokemon+go
    • http://zs.tom.ru/jsplugins/ckfinder/userfiles/files/jifiludoworotal.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_off0000c5f5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC5F5 16792 bytes
font_01_sfnt_off0000de0c.bin
cda1133b3b8b69f7898acdca7a7aba82252d208d94f40c6f47a2b37f72301def
pdf-font-stream PDF embedded font (sfnt) at offset 0xDE0C 10976 bytes
font_02_sfnt_off0000f7a4.bin
c03fa824597823332507d579a9164b80c8bc8f5a394d7061bf7273c016bf3315
pdf-font-stream PDF embedded font (sfnt) at offset 0xF7A4 19288 bytes