Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4787f1346253d26…

MALICIOUS

PDF

80.3 KB Created: 2021-09-16 23:54:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: a73ef17b55675bf6ca70566e3dfacb73 SHA-1: 7dfe8400e52edfcfbaea9571b7e1c864761db5d4 SHA-256: f4787f1346253d26fa4a92c868d7a20c6a71fb410ba6f3c802460d73c9610dec
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs pointing to various domains, many of which appear to be compromised or disposable hosting, suggesting a link farm or phishing lure. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically highlights this behavior, indicating the PDF's purpose is to redirect users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://infrive.ru/uplcv?utm_term=how+to+shift+apps+to+sd+card PDF link annotation
    • https://biomisszio.hu/tmp/wikagugejitiv.pdfIn PDF document text
    • http://newdimension.su/userfiles/file/84225069229.pdfIn PDF document text
    • https://cordovajewelry.com/images/file/87979463071.pdfIn PDF document text
    • http://aodaiminhhanh.com/app/webroot/uploads/files/46270886387.pdfIn PDF document text
    • http://schuetzenfest-hemeringen.de/ablage/userfiles/files/73749168277.pdfIn PDF document text
    • http://austral-immo.com/userfiles/files/92707225310.pdfIn PDF document text
    • http://www.smartlandgroup.com/ckfinder/userfiles/files/93120552611.pdfIn PDF document text
    • https://khanikango.in/file/jojinapit.pdfIn PDF document text
    • http://www.aceitunasdelguadalhorce.es/ckfinder/userfiles/files/wadej.pdfIn PDF document text
    • http://www.peplex.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613b552db06d4---24437413300.pdfIn PDF document text
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a7b886f58a---12188876403.pdfIn PDF document text
    • http://mazdooradda.com/userfiles/file/bidekege.pdfIn PDF document text
    • http://klaaswester.nl/img/file/kuliwakipuz.pdfIn PDF document text
    • http://pass38.com/images/contentimages/files/59167418400.pdfIn PDF document text
    • https://bursakaynak.com/userfiles/file/xasid.pdfIn PDF document text
    • http://nifaelectronics.com/userfiles/file/94245137445.pdfIn PDF document text
    • http://maymaygiaydachidang.com/upload/files/44123833531.pdfIn PDF document text
    • http://mindennapi.hu/upload/file/45785248302.pdfIn PDF document text
    • https://balaji-technology.com/userfiles/file/zovegenivojizulomulofajo.pdfIn PDF document text
    • http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140e4f923ef2---wumuma.pdfIn PDF document text
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133275963fff---36882295462.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_off0000d663.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD663 17496 bytes
SHA-256: 5e8e47086b900b312f87fb5df0a93a76bfdfe9bc86308576b6221c00e8f1659d
font_01_sfnt_off000103d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103D0 10512 bytes
SHA-256: 3d5e41af00645640b05514c6ece0eb314be11ccf94246dcb1f28cbd2fdfc1e45
font_02_sfnt_off00011bed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BED 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1