Malicious PDF — malware analysis report

Static analysis result for SHA-256 92f1c738bfe2b43b…

MALICIOUS

PDF

71.9 KB Created: 2021-09-25 12:26:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 66eac59ab7b82f74bbbce3beaffc0381 SHA-1: 46d0ce45fb24c1df5e97f477f854f90748d1d97e SHA-256: 92f1c738bfe2b43b674e59fa08c5d0c87aea732834be5b8165509f2011449a59
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to compromised or disposable hosting domains, indicative of a link farm designed to lure users to malicious sites. Heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' strongly suggest this malicious intent. The ML classifier and ClamAV detection further confirm the malicious nature of the file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 https://chcial.ru/uplcv?utm_term=android+upload+photo+to+facebook
    • http://energyexcess.com/userfiles/file/tisulilazenepova.pdf
    • http://alpes-maritimes.proximeo.com/ckfinder/userfiles/files/gijilu.pdf
    • https://amityhr.com/userfiles/file/16718385330.pdf
    • https://butchercurnow.com/img/shop/contents/99880049356.pdf
    • http://marinaxaraes.com.br/ckfinder/userfiles/files/miwotom.pdf
    • https://www.grandeprairie.org/wp-content/plugins/formcraft/file-upload/server/content/files/1612ea3de7cac7---dewut.pdf
    • http://propack-th.com/image/upload/File/dojerifozejojutez.pdf
    • http://icmasistemas.com/userfiles/files/42193236146.pdf
    • https://netcsemege.hu/ckfinder/userfiles/files/zakoxegesinugibilivenoxa.pdf
    • http://studiotecnicomartani.eu/userfiles/files/94836314962.pdf
    • http://conomiya.com/images/uploadedimages/file/borobogodepemobogewaguv.pdf
    • http://vietcem.vn/public/default/ckeditor/files/jutulo.pdf
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614ae859ba999---rigora.pdf
    • http://komputerzagrosze.pl/userfiles/file/46540079257.pdf
    • https://birsamundapark.in/userfiles/files/batoga.pdf
    • http://biosafety.biz/ckfinder/userfiles/files/vopizibevudewotemi.pdf
    • http://xn----7sbakif2a3azdub.xn--p1ai/admin/ckfinder/userfiles/files/ravaropetepabutevenu.pdf
    • http://nexxosrealty.com/userfiles/files/pefanewefobuwelile.pdf
    • http://smart.sut.ac.th/tsme/src/lib/ckfinder/userfiles/files/kevakujutobatalovogon.pdf
    • https://thokhoavietnam.com/upload/files/matipalezukemusapeg.pdf
    • https://kotypsy.pl/ckfinder/userfiles/files/digikunojezu.pdf
    • http://ketphatthinh.vn/upload/files/gadig.pdf
    • https://immo-cjeanpaul.lu/userfiles/files/defojomuturanomow.pdf
    • https://haps.company/wp-content/plugins/super-forms/uploads/php/files/e52e17391ce9316cbacb97a6d0bdaa96/22420391638.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_off0000b56c.bin
d225aa8b4cebd6836472f6d09002e7c9a96fdb60af83e00204543d920cbd024d
pdf-font-stream PDF embedded font (sfnt) at offset 0xB56C 17080 bytes
font_01_sfnt_off0000e14f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE14F 16792 bytes
font_02_sfnt_off0000f966.bin
34b5194c624e282a1b3b159a7a0e876745f73b728369ebf0773ff01356874b9c
pdf-font-stream PDF embedded font (sfnt) at offset 0xF966 10860 bytes