Malicious PDF — malware analysis report

Static analysis result for SHA-256 f93a4e676d0e2308…

MALICIOUS

PDF

71.3 KB Created: 2021-09-15 18:05:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 24686ad9d622fb763b04000e673a298e SHA-1: c6f691033e8e5a090ac7a733cedd7bea3f0fc1ef SHA-256: f93a4e676d0e23083489dcdd1006cf59932fd6f368ed6053b1c15c5d3dda7b55
156 Risk Score

Malware Insights

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

The PDF contains numerous external URIs and is identified as a link farm, with several links pointing to compromised CMS upload storage. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is unreadable, but the heuristics and URLs are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://drafthe.ru/uplcv?utm_term=how+to+make+a+slow+motion+video+on+android PDF link annotation
    • https://pmeds.us/userfiles/file/lurotuwesinipopinovatodar.pdfIn PDF document text
    • http://snailgame.ru/upload/files/20210913090325.pdfIn PDF document text
    • http://bjavc.com/filespath/files/20210903182917.pdfIn PDF document text
    • http://wcsps.com.tw/ckfinder/userfiles/files/10125401733.pdfIn PDF document text
    • https://goez3.com/10005001208290177/ckfinder/userfiles/files/sejiwukorefudaxubabi.pdfIn PDF document text
    • https://venusnvs.com/userfiles/file/daduzimobiromor.pdfIn PDF document text
    • https://woft-dining.com/webroot/editor-uploads/files/laxugan.pdfIn PDF document text
    • http://deurwater.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130ed5023cc0---55372900524.pdfIn PDF document text
    • http://www.dfdtrading.sk/ckfinder/userfiles/files/6539179965.pdfIn PDF document text
    • http://gesundimjob.at/images/content/files/56700146395.pdfIn PDF document text
    • http://zrdb-drogbud.pl/Upload/file/83563437781.pdfIn PDF document text
    • http://accronline.com/userfiles/file/87857065211.pdfIn PDF document text
    • https://tigaintan.com/contents/files/jobutinuxireki.pdfIn PDF document text
    • http://7sate.com/filespath/files/20210912022703.pdfIn PDF document text
    • https://izometal.net/mm/file/92458845098.pdfIn PDF document text
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613886a894bd3---xipizekoketadefemilur.pdfIn PDF document text
    • https://rajaketiga.com/contents/files/gutiminagisedidagakan.pdfIn PDF document text
    • http://www.egymast-segito.hu/uploaded/fck/file/2069550599.pdfIn PDF document text
    • http://gourmethousemacau.com/UploadFilesfile///tagakugiwipu.pdfIn PDF document text
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131fde8c13da---lubitawuguvenijekabuvi.pdfIn PDF document text
    • http://iraneto.com/basefile/iranetocom/files/15818780656.pdfIn PDF document text
    • https://bibonatura.com/ckfinder/userfiles/files/ligejibofiwopibuzuw.pdfIn PDF document text
    • https://dangeloremodeling.com/nbloom/fckuploads/file/navamuxito.pdfIn PDF document text
    • 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_off0000b3a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3A6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cbb8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBB8 16832 bytes
SHA-256: 14afc18dd6a4bdd39ab659f38f6461d6adafd0833a64ca5cfe45bb88e3cfa256
font_02_sfnt_off0000f716.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF716 10644 bytes
SHA-256: 2358f926e488bf715eecdc880c186c5d3dc8eb48952ed09ea9f55327fe97e4c9