Malicious PDF — malware analysis report

Static analysis result for SHA-256 42ca1b2d5c446d69…

MALICIOUS

PDF

72.1 KB Created: 2021-09-29 09:22:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 03f499a3900265f3b23dc5e65aa20bff SHA-1: 1b224e05f3a231a14497d580224c4ae6e5982c55 SHA-256: 42ca1b2d5c446d69ff388467767044cc1feeba6437b9d3ed59e3db0f873f2ebf
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF file contains numerous embedded URLs that form a link farm, with many pointing to compromised CMS uploads or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The primary attack pattern involves tricking users into visiting these external, potentially malicious, websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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://drafthe.ru/uplcv?utm_term=top+15+most+populous+countries PDF link annotation
    • http://nwatchonline.com/userfiles/file/tikebakozowuwosuxawal.pdfIn PDF document text
    • http://rsst77.ru/upload/files/fuzupopude.pdfIn PDF document text
    • http://assisdrive.pt/userfiles/file/goxanokujuduf.pdfIn PDF document text
    • https://luatsubienhoa.com/upload/ck/files/48090067288.pdfIn PDF document text
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/plutplj15lv2emhf5vdotv0n56/fitewotesunesemejevelekix.pdfIn PDF document text
    • https://www.ccps.mx/wp-content/plugins/super-forms/uploads/php/files/90c8ee588a0db7b3ecd535a3024c4ee4/1453784462.pdfIn PDF document text
    • https://hotelharmika.com/assets/userfiles/files/90211768731.pdfIn PDF document text
    • http://peak-experience-japan.com/images/blog/file/94549547236.pdfIn PDF document text
    • http://www.rebranded.tv/wp-content/plugins/formcraft/file-upload/server/content/files/161414d05eb810---vafonojananu.pdfIn PDF document text
    • http://groupementpecheduloir.com/ckfinder/userfiles/files/33117723829.pdfIn PDF document text
    • http://nakajima-ya.com/upload/save_image/files/lemaguvekesez.pdfIn PDF document text
    • http://vietcem.vn/public/default/ckeditor/files/varutipasawi.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/4145760288.pdfIn PDF document text
    • https://calendarsunrooms.com/userfiles/files/36438398481.pdfIn PDF document text
    • https://siphouse96.com/wp-content/plugins/super-forms/uploads/php/files/d94123409846ef7bf3e22add72329f44/50253588799.pdfIn PDF document text
    • http://kjphotocon.org/data/userfiles/files/gexilikadil.pdfIn PDF document text
    • https://simplehome.ro/ckfinder/userfiles/files/roxatas.pdfIn PDF document text
    • https://www.rogierstoel.nl/wp-content/plugins/super-forms/uploads/php/files/2q6a3g9n5fcchovchkmrs7noaa/dupawejuj.pdfIn PDF document text
    • https://dukeofmarshall.com/ckfinder/userfiles/files/perisugenobaxelijamedinez.pdfIn PDF document text
    • http://copy-office.it/userfiles/file/85172998727.pdfIn PDF document text
    • http://www.nbc.com.vn/ckfinder/userfiles/files/70615564212.pdfIn PDF document text
    • https://drhuanghair.com/uploads/files/202109230936268606.pdfIn PDF document text
    • https://salvamontbihor.ro/app/webroot/files/userfiles/files/31080591013.pdfIn PDF document text
    • https://stratasphere.online/userfiles/file/veperuwamesulajutek.pdfIn PDF document text
    • https://www.peltonfell.org.uk/ckfinder/userfiles/files/vakunifazalebemaxalidabi.pdfIn PDF document text
    • http://qlinairnv.be/userfiles/file/danevo.pdfIn PDF document text
    • 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_off0000b60d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB60D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ce24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE24 10620 bytes
SHA-256: 1887d403b3c3c5a57220d91327766e68b6becf6ab4d23b048058d6c26da3e44d
font_02_sfnt_off0000e680.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE680 17888 bytes
SHA-256: 17ef5228facd20a16de0dd4cb7309514933f163946eba3335e728a44494d5218