Malicious PDF — malware analysis report

Static analysis result for SHA-256 6cfd1bbc22c28b50…

MALICIOUS

PDF

81.0 KB Created: 2021-09-06 09:04:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 8d1493ca35c8dfcf6e67fe723f691539 SHA-1: 643f4a16e0e8b34a50dda782f528556ddef6c82c SHA-256: 6cfd1bbc22c28b50825ec4cd401ed1e94ee08ebe217fb06dd1dde55efe2c8627
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external resources, many of which point to compromised CMS upload directories or are hosted on disposable domains, indicating a link farm designed to distribute further malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://recapress.com/ckfinder/userfiles/files/68944928782.pdf In PDF document text
    • https://gz-topstar.com/wp-content/plugins/super-forms/uploads/php/files/cf8aa9ee6bca92b81903dac2724d6b34/najesexemifigetututezup.pdfIn PDF document text
    • http://investinwielkopolska.pl/application/lib/ckfinder/userfiles/files/kesudabep.pdfIn PDF document text
    • https://www.hausbootgeiseltalsee.de/wp-content/plugins/super-forms/uploads/php/files/f80h23im34q06pnb92njijhibj/revubupenejufuxuk.pdfIn PDF document text
    • https://www.isnb.co.uk/wp-content/plugins/super-forms/uploads/php/files/edf94034838ad6afc3760f083cce2b8c/vawefedewubuxukatobopeko.pdfIn PDF document text
    • http://iccj.jp/images/uploads/fckeditor/file/18680425432.pdfIn PDF document text
    • https://snf.styleguides.ch/userfiles/files/22904947243.pdfIn PDF document text
    • https://universal4shipping.net/userfiles/file/rumorom.pdfIn PDF document text
    • http://ventima.ru/userfiles/file/pevonireref.pdfIn PDF document text
    • http://etenindex.nl/images/uploads/rukek.pdfIn PDF document text
    • http://xn----7sbab1bcaqplb0ccyi9d.xn--p1ai/files/file/mexopami.pdfIn PDF document text
    • http://al-bandak.com/userfiles/file/lusal.pdfIn PDF document text
    • http://gibisch.biz/files/files/gawegalusujanunesuxogi.pdfIn PDF document text
    • https://graffitipaintstudio.com/wp-content/plugins/super-forms/uploads/php/files/a9dda665768d6a18614c6e15c4add63d/6611369223.pdfIn PDF document text
    • https://ecowaytechnologies.com/ckfinder/userfiles/files/73159262240.pdfIn PDF document text
    • http://tecs4.com/intranet/ckfinder/userfiles/files/zolilotefosomurud.pdfIn PDF document text
    • https://leicht-spb.ru/wp-content/plugins/super-forms/uploads/php/files/ad1b3daa5ac60708cf6c6648ff341031/1305604359.pdfIn PDF document text
    • http://abwvictory.com/uploads/files/26176133367.pdfIn PDF document text
    • http://albino-pitti.com/pub_img/file/tuleladiwerovezutemuja.pdfIn PDF document text
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160ae9502329eb---57818416290.pdfIn PDF document text
    • https://bursac.net/userfiles/file/nezul.pdfIn PDF document text
    • http://unicorn-furnitures.com/d/files/pomuxadolojunanij.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=calculating+prices+using+discounts+worksheetPDF 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_off0000d492.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD492 11104 bytes
SHA-256: 49832e499cc545021e3cd448b2178b30cfec05e47683f967adfb78166ce784fa
font_01_sfnt_off0000ee45.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE45 18280 bytes
SHA-256: d9cecb741649c6745e54e43aff7afe59d66630898e4c8aa2afd9968ec9918f29
font_02_sfnt_off00011e61.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E61 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1