Malicious PDF — malware analysis report

Static analysis result for SHA-256 dc27f85a0211d99a…

MALICIOUS

PDF

67.9 KB Created: 2021-09-24 20:13:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 7f29e9d9f7512d0093c6635c26c80098 SHA-1: 624f0cf940bc42f86b3c53663ea0d2119c6dd913 SHA-256: dc27f85a0211d99aa30d55c8a7bc697f21644c0ce8f39e53d5e592dd05034332
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a phishing or trojan payload. It functions as a link farm, with numerous embedded URLs pointing to compromised WordPress sites that host further PDF files. These secondary PDFs likely serve as lures for phishing attacks or to download additional malware. The document body is heavily obfuscated and unreadable, providing no direct content clues.

Machine Learning

  • Nyx PDF Classifier malicious score 0.6526

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
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser failed: PDFSyntaxError. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.
  • 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://coretry.ru/uplcv?utm_term=how+to+do+a+screenshot+on+a+samsung+galaxy+s3 PDF link annotation
    • http://quickfix-poland.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613967b7183bc---20912897596.pdfIn PDF document text
    • https://go2germany.ru/files/file/19195070919.pdfIn PDF document text
    • https://swotin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614df71916598---85602800588.pdfIn PDF document text
    • http://andlupa.com/userfiles/file/14340548526.pdfIn PDF document text
    • https://psychologgia.pl/Upload/file/26849491262.pdfIn PDF document text
    • http://orderleesushi.com/uploads/files/46494030503.pdfIn PDF document text
    • https://neurondevelopment.org/userfiles/file/nirexiwugokasavimatugizan.pdfIn PDF document text
    • https://tktravelkorea.com/FileData/ckfinder/files/20210913_9E116CF3C86DFFE0.pdfIn PDF document text
    • https://genesisbehaviorcenter.com/wp-content/plugins/super-forms/uploads/php/files/832a50a69882eae60eb16d2546990049/65274052363.pdfIn PDF document text
    • https://queensflower.nl/clientfiles/23622341979.pdfIn PDF document text
    • https://nieruchomosciprzetargi.pl/files/file/gurezaxifiwapedikifisunak.pdfIn PDF document text
    • http://arniestribu.com/campannas/file/29974175076.pdfIn PDF document text
    • https://proetcontra.hu/userfiles/file/dopikeximanev.pdfIn PDF document text
    • http://ekachaiguitarist.com/ckfinder/userfiles/files/vodofulata.pdfIn PDF document text
    • https://willes-gb.com/uploads/files/202109061323444089.pdfIn PDF document text
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/16136898464ccf---37891200916.pdfIn PDF document text
    • https://perleyparish.org/wp-content/plugins/super-forms/uploads/php/files/50aef777e921cde01ce2516e3fd85997/jebimuvizopirubafide.pdfIn PDF document text
    • http://ztkammer.at/uploads/file/38164908547.pdfIn PDF document text
    • http://allasclub.com/campannas/file/66614009728.pdfIn PDF document text
    • http://stepasidemedical.com/images/uploads/file/4727969840.pdfIn PDF document text
    • http://ogledalata.bg/uploads/pages/files/rolafom.pdfIn PDF document text
    • https://cradlegold.com/wp-content/plugins/super-forms/uploads/php/files/c8huh806s7gd2b8boq7r8r08gc/rawokijupid.pdfIn PDF document text
    • http://konferencii.org/web/uploads/assets/file/5634109163.pdfIn PDF document text
    • https://pepsima.biz/files/file/54730415201.pdfIn PDF document text
    • http://timeyear-v.com/userfiles/file/numimakefosiratomewi.pdfIn 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_off0000b45f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB45F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cc76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC76 11288 bytes
SHA-256: 608cef4b891f84dceddf134f8d6684de447a77ecefb46a13e9cf8b30efbe90d5
font_02_sfnt_off0000e6b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6B2 15468 bytes
SHA-256: a60ec29ea7975b56a45d605022087889a92f8c93f1cbd41decee529d903e1dca