Malicious PDF — malware analysis report

Static analysis result for SHA-256 881a7bf8c7a3204f…

MALICIOUS

PDF

83.1 KB Created: 2021-08-27 20:48:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 331b9820705b61e4ec8b641d288bb2ce SHA-1: 0b928cb39751f2303cb5530f7abd4d9c066ddf62 SHA-256: 881a7bf8c7a3204f78c0426fc4bad6f453595f6430c60b97b91f7821171e3dd4
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 compromised WordPress sites and disposable hosting domains. The embedded URLs likely serve as lures for phishing attacks or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://cructi.ru/uplcv?utm_term=columbo+with+george+wendt
    • https://fobiy.net/wp-content/plugins/super-forms/uploads/php/files/f14daff04caa311cdb26d0827fed02c8/wanefosafipubuzemete.pdf
    • http://5m-tti.com/uploads/image/files/dulasos.pdf
    • https://www.xcelsus.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c1657f6a27d---woxiwexofewadumexumis.pdf
    • http://www.pzkexie.com/up_files/file/bonunarudevove.pdf
    • http://shqinze.net/admin/upimg/file///90496189001.pdf
    • http://sinara.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c487c66c43e---27111320002.pdf
    • https://caribemed.com/userfiles/file/32219864574.pdf
    • http://rulada.by/upload/editor/files/97482358563.pdf
    • http://rigassprotes.lv/uploadz/file/88223838675.pdf
    • http://exhibitionchannel.com/upload/gudidububeketal.pdf
    • http://sumbulefendiegitimvakfi.com/resimler/files/laketilan.pdf
    • http://paraleumarian.ro/app/webroot/files/userfiles/files/23068090950.pdf
    • http://matonaklawfirm.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/guloluwalabajiluduza.pdf
    • http://www.afamaresme.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a404fc416f4---34319139306.pdf
    • http://solee56.com/ckfinder/userfiles/files/91510230537.pdf
    • https://n95america.com/wp-content/plugins/super-forms/uploads/php/files/584e035bd402e9cc4e0e6a8849a945c9/4527538213.pdf
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1611e1c02bd696---zotogudiripisa.pdf
    • http://shreyaghoshal.com/konadnew/userfiles/file/22723464176.pdf
    • http://carlaschroyen.com/content_docs/68020661321.pdf
    • https://www.movingwithmagna.com/wp-content/plugins/super-forms/uploads/php/files/5c9cadf06e0cafcd1617b3ad96cf4873/56723565592.pdf
    • http://thepducphat.com/upload/files/razaposokituwevovudodijub.pdf
    • http://nakatka.com/files/file/jipujuxixivarusikedafutaf.pdf
    • http://chizclean.ru/files/fck/file/neforupuka.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_off0000df99.bin
1a21218ac4f7d9def02b97c72f849ba97f6d7c01c54f5c5b975a543d1acecbed
pdf-font-stream PDF embedded font (sfnt) at offset 0xDF99 10720 bytes
font_01_sfnt_off0000f7dc.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF7DC 16792 bytes
font_02_sfnt_off00010fee.bin
fba91d588d3111155ee1484491b2dce5801ed068fea8baa2f056bea0bb1b52b4
pdf-font-stream PDF embedded font (sfnt) at offset 0x10FEE 18064 bytes