Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b3f75313dd940a2…

MALICIOUS

PDF

75.0 KB Created: 2021-08-11 12:29:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 10b1b83b254299a509242f10438a3800 SHA-1: f5d09713b370127b798a1d2d5764ca74cad51093 SHA-256: 3b3f75313dd940a2480106febaaf963c02aed530bb943d73f13ca226bd28c326
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document identified as malicious by ClamAV and an ML classifier. It contains numerous external URIs and is described as a link farm on disposable hosting, suggesting an attempt to redirect users to malicious sites. The presence of PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristic indicates links pointing to compromised WordPress upload storage, further reinforcing the malicious intent. No scripts were extracted, but the overall structure and URL patterns are indicative of a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://allytemp.ru/uplcv?utm_term=benim+hocam+tarih+pdf+notlar%C4%B1 PDF link annotation
    • https://www.dyna-tech.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160f493d0c8e03---virizi.pdfIn PDF document text
    • https://activepymes.com/pub/file/59779892056.pdfIn PDF document text
    • http://www.lentilles-progressives.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160b602110b5fb---2392458882.pdfIn PDF document text
    • https://benchmarktransitions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a95f1f62a01---poxusufilebe.pdfIn PDF document text
    • http://noospc.ru/SITE/files/editor/file/19800316713.pdfIn PDF document text
    • http://navigator-nsk.ru/userfiles/file/tokugiworamekewif.pdfIn PDF document text
    • http://duetsepolno.pl/userfiles/file/vigexixemofizagipepazisaj.pdfIn PDF document text
    • https://vivaldiroberto.com/img/files/mediafiles/file/dowopuk.pdfIn PDF document text
    • http://deeringbayrealestate.com/userfiles/files/moxixigavekig.pdfIn PDF document text
    • http://bookblog.kr/data/file//files/silizimepuku.pdfIn PDF document text
    • https://gamedunyasi.com/calisma2/files/uploads/zolonobosugerasifabanomuj.pdfIn PDF document text
    • https://watfordfairtrade.org/app/webroot/img/files/disarozegaz.pdfIn PDF document text
    • http://www.serenissimaservizi.com//files/24317152217.pdfIn PDF document text
    • https://www.cpro.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160778917353b8---kebapexuzasuledumil.pdfIn PDF document text
    • http://thermcom.cz/userfiles/file/11934833726.pdfIn PDF document text
    • http://www.gainerwindows.ca/wp-content/plugins/super-forms/uploads/php/files/k5t1j127bh0rqecof2pdt8uv06/46318947536.pdfIn PDF document text
    • http://agcslohian.com/userfiles/file/38126606608.pdfIn PDF document text
    • https://arnetbilgisayar.com/upload/ckfinder/files/denirabad.pdfIn PDF document text
    • https://cspdental.com/wp-content/plugins/super-forms/uploads/php/files/9bb92ebd1400f3df562021b412ecd940/57618455195.pdfIn PDF document text
    • https://tranduongauto.com/app/webroot/files/images/pages/files/gufedolivutizusefineze.pdfIn PDF document text
    • http://www.idenet.net/wp-content/plugins/formcraft/file-upload/server/content/files/16072d51843547---44936898132.pdfIn PDF document text
    • http://aclamerica.com/customers/CMS-IMAGES/file/70276236191.pdfIn PDF document text
    • http://xn--zb0bw3kv4s8mn.com/upload/fckeditor/file/fepimukafofilogikezujekew.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_off0000bf9d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF9D 17944 bytes
SHA-256: 55d14353fbf7958acbcd729e82e7020f1882228050fc74e0262a5215fa0d87c3
font_01_sfnt_off0000eb2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB2D 10816 bytes
SHA-256: a2a5d07fe8f3d74d59163b9c90d7dc9812b55b38e92ed5efa16c6571111a8a1d
font_02_sfnt_off000103d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103D8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1