Malicious PDF — malware analysis report

Static analysis result for SHA-256 158dfe8d081a9f9f…

MALICIOUS

PDF

68.6 KB Created: 2021-09-13 12:38:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: ca777f03528c8c479bd046eac483d1c0 SHA-1: 0e4d5502b8fa28e7638c1bdff2c9a50dee37db87 SHA-256: 158dfe8d081a9f9fd560d0116ccafdca0bd28b954ed2019299f7ba40a498e282
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF is identified as malicious by ClamAV and an ML classifier, exhibiting characteristics of a phishing lure. It contains numerous links to external websites, many hosted on compromised CMS platforms or disposable domains, suggesting an attempt to redirect users to malicious content. The document body is heavily obfuscated and unreadable, but the presence of multiple external links and the overall structure strongly indicate a phishing or credential harvesting attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 2 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 http://zs-oilfieldequip.ru/d/files/50389634314.pdf In PDF document text
    • https://www.karenlovelee.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613059229cf15---dugifo.pdfIn PDF document text
    • https://www.natursany.com/ckfinder/userfiles/files/68147514110.pdfIn PDF document text
    • http://tecs4.com/intranet/ckfinder/userfiles/files/ligaviwibu.pdfIn PDF document text
    • http://quickfix-poland.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e693bdca7a---seniviloxakelajub.pdfIn PDF document text
    • https://ms2oke.com/contents/files/94263186095.pdfIn PDF document text
    • https://shipnhanh247.vn/asset/files/29103506762.pdfIn PDF document text
    • http://pes.edu.mn/ckfinder/userfiles/files/53578467058.pdfIn PDF document text
    • http://cameralehiep.com/hinhanh_fckeditor/file/filobepevimope.pdfIn PDF document text
    • https://houstoncoinclub.org/FCKeditor/file/negeminekazive.pdfIn PDF document text
    • http://www.virtualaid.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1613d7801f2fa1---61615621904.pdfIn PDF document text
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/161368ffc8ce63---45073911413.pdfIn PDF document text
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133ce0715448---xoxifalegemaputenuled.pdfIn PDF document text
    • https://giorgiosantinelli.it/file/mofozujaligebotebitasi.pdfIn PDF document text
    • https://ppkh.net/userfiles/file/37137446769.pdfIn PDF document text
    • http://www.sname.org.tw/sname/ckfinder/userfiles/files/10952992031.pdfIn PDF document text
    • http://gediklimakinahidrolik.com/resimler/files/84419784340.pdfIn PDF document text
    • http://xn--80aesyq.xn--p1acf/files/file/91981515648.pdfIn PDF document text
    • https://illustrations.noche.fr/images/files/jaketuxekor.pdfIn PDF document text
    • https://millvalley.com/wysiwygfiles/file/dovefezazawipetibadow.pdfIn PDF document text
    • http://tonyprins.nl/images/uploads/file/numuwejow.pdfIn PDF document text
    • https://vipbeachhouse.com/uploads/editor/file/52893655319.pdfIn PDF document text
    • https://kodeac.com/wp-content/plugins/super-forms/uploads/php/files/psvhvn0jvbacqgd6oto0s4smbr/13099628710.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=swat+4+download+androidPDF link annotation
    • 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_off0000b280.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB280 14164 bytes
SHA-256: ff2510d66790e6cfd2676c618111b9d674c39ae4340edfbfe3cbab24b4453cf6
font_01_sfnt_off0000d5c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5C1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000edd8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDD8 10180 bytes
SHA-256: 27d17dfbab82b64fb822aabb0f6d4dd0f91761b99cfb62947dbc38287a24404d