Malicious PDF — malware analysis report

Static analysis result for SHA-256 9892fbd3c4612c25…

MALICIOUS

PDF

73.2 KB Created: 2021-07-03 06:08:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 28fd6b9a8addafe1048142b15bf7ccf8 SHA-1: b9616eb84080143a3bd543d61440f7d4635e4f58 SHA-256: 9892fbd3c4612c25934bd172141e45d927b6c0323b44f9dae6522bda4f4f24f6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous links pointing to compromised websites, which in turn host other PDF files. This behavior is indicative of a link farm used to distribute malicious content, likely for phishing or malware delivery. The ML classifier and ClamAV detection strongly support the malicious nature of this file.

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://udachi.co.th/wp-content/plugins/super-forms/uploads/php/files/f7hmem2hu32lnci2avh0p80vui/zuvakimikesasedolus.pdf In PDF document text
    • http://thehawthornnyc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e044e429b9---10802373989.pdfIn PDF document text
    • https://betenrealestate.com/sites/default/files/file/busojiw.pdfIn PDF document text
    • http://icmasistemas.com/userfiles/files/jenarajuxijotixewupiw.pdfIn PDF document text
    • http://morgancountyoh.com/userimages/10101614778.pdfIn PDF document text
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160780390c8f8f---mavog.pdfIn PDF document text
    • http://www.korayozelguvenlik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a02a48c056a---popazu.pdfIn PDF document text
    • https://www.webhisto.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160a0b81d67906---23566706151.pdfIn PDF document text
    • http://dejede.com/userfiles/file/tirafapimajafazigapelenad.pdfIn PDF document text
    • http://chetaomaynganhnhua.com/uploads/files/35927980806.pdfIn PDF document text
    • http://www.communityheroesproject.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608133548ad29---92333828617.pdfIn PDF document text
    • https://brothers-music.com/ckfinder/userfiles/files/xesula.pdfIn PDF document text
    • https://aradovan.com/userfiles/file/fufivuritoziwirazozugu.pdfIn PDF document text
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/160a40871ad12c---medole.pdfIn PDF document text
    • http://coopmong.com/ckupload/files/xexixebow.pdfIn PDF document text
    • https://charlesstreetvideo.com/userfiles/file/15406049665.pdfIn PDF document text
    • https://technok.cz/wp-content/plugins/super-forms/uploads/php/files/26274db0f7643e88da47a0b94832df95/widibodagesarak.pdfIn PDF document text
    • http://www.theagentpipeline.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ce24617a1d---gigalig.pdfIn PDF document text
    • http://edu-family72.ru/content/images/uploads/file/zowegotibaru.pdfIn PDF document text
    • http://alhouti.com/userfiles/file/14785418925.pdfIn PDF document text
    • http://brmhn.com/userfiles/file/20210523174854_4pejmr.pdfIn PDF document text
    • http://heilpraxis-pankow.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609eaecb21e12---45947215902.pdfIn PDF document text
    • https://flexrocksrollovers.com/wp-content/plugins/super-forms/uploads/php/files/42pi7e00h7sp2ogvljsusahdnf/14123293234.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=specific+conductance+of+0.1+n+kclPDF 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_off0000b788.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB788 10852 bytes
SHA-256: 7a25be7d549b4775843baf0eb1e383356b657b448ef4b59641c793b22308f35d
font_01_sfnt_off0000d0c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0C0 17392 bytes
SHA-256: 795ce511767e4adb787e855a2e9dfb1105086aeec422ce16afea9f1025ce2372
font_02_sfnt_off0000fe1c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE1C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1