Malicious PDF — malware analysis report

Static analysis result for SHA-256 b9cc32afd9365da4…

MALICIOUS

PDF

68.1 KB Created: 2021-09-24 18:46:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: c644850cf466e1752426cba290bc9fea SHA-1: af287481e6b11dfe80c8d7c2a35f8fa433db7f8b SHA-256: b9cc32afd9365da404a4a72351c3ee9da6f6dde339116f69ac4b57ed3ee891fa
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/lc8ffmjapbrjtiiuhegqbce0pg/9204593418.pdf In PDF document text
    • http://hoachathoanggia.com/userfiles/file/wapetinirosedimaw.pdfIn PDF document text
    • http://gamecoast.by/uploads/files/93136113386.pdfIn PDF document text
    • http://windmill-bv.com/userfiles/files/wagakekoguzafam.pdfIn PDF document text
    • http://vino-charlie.cz/userfiles/file/54796626511.pdfIn PDF document text
    • http://www.sudeshnamaulik.com/fckimages/file/16798127871.pdfIn PDF document text
    • http://bukvoznaika.ru/ckfinder/userfiles/files/46312419527.pdfIn PDF document text
    • https://www.nhabe.com.vn/ckfinder/userfiles/files/30750615841.pdfIn PDF document text
    • http://ykzn8.com/upfiles/editor/files/15754731560.pdfIn PDF document text
    • https://mandalaconfeccao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1614211ee890ae---wejame.pdfIn PDF document text
    • http://studiorumeo.it/userfiles/files/nudibinegubelupaxagufuzim.pdfIn PDF document text
    • http://bjbtrh.com/files/pic/file/tugelanaxikimed.pdfIn PDF document text
    • http://sherwoodonionfestival.com/ckfinder/userfiles/files/83872537573.pdfIn PDF document text
    • http://vantaidongsaigon.com/uploads/files/61495105632.pdfIn PDF document text
    • https://creativesilhouettes.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161394788cbf1c---86259807662.pdfIn PDF document text
    • http://yepuco.com/uploads/files/rokasexuvegejifopozewukid.pdfIn PDF document text
    • http://cherryontop.pl/upload/fotki/file/marebudibanezepobabofu.pdfIn PDF document text
    • https://hunglivet.com/uploads/files/202109180207434855.pdfIn PDF document text
    • https://299-45.com/CKEdit/upload/files/dajaser.pdfIn PDF document text
    • https://tierlistei.ch/downloads/97758072731.pdfIn PDF document text
    • http://genarchi.com/data/temp/file/bugapanuminojegifavugel.pdfIn PDF document text
    • https://sainaudit.mn/File/mozukanefigifon.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=watch+wrong+turn+4PDF 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_off0000ad3a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAD3A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c551.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC551 10328 bytes
SHA-256: f4ed22970497daacfb55bac8a2265132b4906d54ef35e526a192ccd8cb1859cc
font_02_sfnt_off0000dcb0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCB0 15284 bytes
SHA-256: 4f78b3c4b21215e88afb1c28089a949c6cc208fe4f7a737a5314c313a75b77de