Malicious PDF — malware analysis report

Static analysis result for SHA-256 8fd4dac242128ce4…

MALICIOUS

PDF

69.3 KB Created: 2021-10-03 16:07:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: ae4b42847a08c31774ab71a5267182f5 SHA-1: 908f1e248af3ed5b14bf17dbd1f45d0be05985a0 SHA-256: 8fd4dac242128ce42166cf6dd42baf0d9bdf35dd7d84f3063353ffdbc0ebc285
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. Heuristics reveal it functions as a link farm, directing users to multiple compromised websites, including one hosted on a WordPress upload storage. The presence of numerous unknown URLs suggests a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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 http://hightopeducation.com/cms_uploaded/file/mulakexejeka.pdf In PDF document text
    • http://swaving-stalinrichting.nl/ckfinder/userfiles/files/gefenunosezeremakaf.pdfIn PDF document text
    • https://e-room.co/userfiles/file/90481473319.pdfIn PDF document text
    • https://eirai.org/editor/ckfinder/userfiles/files/dodeguxofifamizaj.pdfIn PDF document text
    • http://kht.civilkozpont.hu/uploads/file/98387195292.pdfIn PDF document text
    • http://kpotplace.com/uploads/files/bojusokanivikavegufegon.pdfIn PDF document text
    • https://liguecasa.mmsfoot.com/stock/file/49439917783.pdfIn PDF document text
    • https://mikludava.lt/images/files/jorenaparofuperijimode.pdfIn PDF document text
    • http://meimagedance.tw/ufiles/files/sakumewu.pdfIn PDF document text
    • http://modernplating.com/userfiles/file/pomalapakimazotuzu.pdfIn PDF document text
    • http://paintingservicesonline.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161379ca99c747---10942896418.pdfIn PDF document text
    • https://www.goldenplanet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1614175a9015c4---femanonimefu.pdfIn PDF document text
    • http://vkp.ru/upload/global/file/bowonusodipojuverexobid.pdfIn PDF document text
    • http://1544-7419.net/upload/fckeditor/file/mewakisumolubexubekup.pdfIn PDF document text
    • https://qud27rxl1-k61l.com/contents/files/lubibesu.pdfIn PDF document text
    • http://hoya-system.com/uploads/files/202109041406197194.pdfIn PDF document text
    • http://www.next-conseil.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16151b95a8ffb0---gotonanumajuko.pdfIn PDF document text
    • https://alrashed-alsaleh.com/userfiles/files/beridiwamebabonojag.pdfIn PDF document text
    • https://www.emmabowman.com/wp-content/plugins/super-forms/uploads/php/files/27c2af513c8a23f9c36bb16a1ae26af4/38692823173.pdfIn PDF document text
    • https://www.servicespace.org/inc/ckfinder/userfiles/files/xavirilaku.pdfIn PDF document text
    • http://laxycoffee.com/upload/files/rupezorumegalikujiziwuwu.pdfIn PDF document text
    • http://rvhifi.cz/files/file/43281556075.pdfIn PDF document text
    • http://hockjoohin.com/admin/uploads/file/90004669303.pdfIn PDF document text
    • http://byty-pardubice.eu/UserFiles/File/53502646030.pdfIn PDF document text
    • https://www.simplythebestevents.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161387d0185aaa---karig.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=tonsillectomy+risks+childPDF 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_off0000b172.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB172 10640 bytes
SHA-256: 9512fbf7d328b8fa0e4685d8bf2208a986155dab1efe8c1e3aabf53dfa729d7a
font_01_sfnt_off0000c9a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9A1 15116 bytes
SHA-256: 97e48c06238280be0eedf07940179f1c866e05b61943e7f4d9f3129149c2c833
font_02_sfnt_off0000efca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFCA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1