Malicious PDF — malware analysis report

Static analysis result for SHA-256 21098cf8972f3439…

MALICIOUS

PDF

79.0 KB Created: 2021-09-08 16:00:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: f3c1e2155afae823154c872b200853ca SHA-1: 24cc26de49bd6d571685a9a2224e57a52e3d3e2f SHA-256: 21098cf8972f3439d294246a8ab1f2b4f96b873bae65d27888fc0ab796735217
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. It contains numerous links pointing to compromised WordPress sites and other domains, suggesting a link farm designed to redirect users to malicious content. The PDF structure and link farm behavior are consistent with phishing or malware distribution campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9958

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://queure.ru/uplcv?utm_term=grandparents+day+worksheets PDF link annotation
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16134843f1941f---tumezamimapol.pdfIn PDF document text
    • http://hsaltsj.com/uploads/files/zinavuvojakugo.pdfIn PDF document text
    • http://fongyoskert.hu/userfiles/files/22259464720.pdfIn PDF document text
    • https://deitratech.com/userfiles/file/retitipelogot.pdfIn PDF document text
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613372c683264---17909421905.pdfIn PDF document text
    • http://sithome.com/upfiles/file/20210905195724.pdfIn PDF document text
    • https://futuresbuilder.net/dayafter/uploadimages/newsimages/file/36170396608.pdfIn PDF document text
    • https://kanalprofi.at/UserFiles/file/rebibubufulesa.pdfIn PDF document text
    • http://geoodwierty.pl/files/file/90176351239.pdfIn PDF document text
    • http://ngocphuocjsc.com/public/default/ckeditor/files/pefetasuromonipof.pdfIn PDF document text
    • https://nada70.org/userfiles/file/93918547828.pdfIn PDF document text
    • http://acsalma.hu/userfiles/files/kepakopovadezegu.pdfIn PDF document text
    • http://erictex.com/ufiles/files/3986497670.pdfIn PDF document text
    • https://triangle-electronics.com/assets/userfiles/file/78526509707.pdfIn PDF document text
    • http://lamexmarket.com/uploads/files/95406649263.pdfIn PDF document text
    • http://thetestmag.com/userfiles/files/kavazi.pdfIn PDF document text
    • http://vertracapital.com/uploads/files/lamelalaboxusumudi.pdfIn PDF document text
    • http://abwmarlboropike.com/uploads/files/pifenunid.pdfIn PDF document text
    • http://bytip.net/filespath/files/20210903123016.pdfIn PDF document text
    • http://www.fotografoeventimilano.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133f13b762f7---91703189677.pdfIn PDF document text
    • https://299-45.com/CKEdit/upload/files/76921327700.pdfIn PDF document text
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/06c7328467b728b74e270a67bef23a7b/vuxojalesufag.pdfIn PDF document text
    • https://jbdclothiers.net/emailer/userfiles/file/45984856308.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_off0000d27c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD27C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ea8e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA8E 17144 bytes
SHA-256: fae6a602fdc8244e0fc892fef165ab5b3b2ecbad250efa1ae0cc9a05dc7b40ac
font_02_sfnt_off0001161e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1161E 10684 bytes
SHA-256: 479d747f608e12096cb956d96b84e4179bd86258cebe72858736636a60fdff17