Malicious PDF — malware analysis report

Static analysis result for SHA-256 c2ff42584d5f3166…

MALICIOUS

PDF

84.9 KB Created: 2021-09-07 02:09:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: ca1f025ae8875853112e7afe76662c12 SHA-1: 01498ccebc5195f47ba3426102ffde354bc2dbfb SHA-256: c2ff42584d5f3166e74697a4243746ab93eb7016f6c9ccd8d0870a54cd15b870
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains numerous embedded URLs that point to compromised WordPress sites, indicating it functions as a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The presence of multiple distinct hosts and the use of 'utm_term' parameters suggest an attempt to obscure the ultimate destination and potentially leverage SEO for distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://chcial.ru/uplcv?utm_term=general+principles+of+taxation+in+the+philippines+pdf PDF link annotation
    • http://www.ebsjosepirosamaria.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075a1f643d42---benoboxexororimibexawit.pdfIn PDF document text
    • http://nakajima-ya.com/upload/save_image/files/82367645179.pdfIn PDF document text
    • http://www.zopfitravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3b7dc4db96---21905386934.pdfIn PDF document text
    • http://www.iamgoingto1996.com/wp-content/plugins/formcraft/file-upload/server/content/files/160734ff8b8910---xikumujavedowefolosux.pdfIn PDF document text
    • http://budohurtsa.pl/userfiles/file/94346539423.pdfIn PDF document text
    • https://proektasis.gr/admin/spaw2/uploads/files/takonumozup.pdfIn PDF document text
    • https://thokhoavietnam.com/upload/files/guwokuxadavovusik.pdfIn PDF document text
    • http://www.thelawchamber.com/wp-content/plugins/formcraft/file-upload/server/content/files/160befb8983e2a---60068621668.pdfIn PDF document text
    • https://www.potterycommercials.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160833e1675a99---tifezagewajajig.pdfIn PDF document text
    • http://rdmsrl.it/userfiles/files/batinomeraputuse.pdfIn PDF document text
    • http://naturestuff.nl/siteimages/file/62929707889.pdfIn PDF document text
    • https://postele-z-masivu.sk/ckfinder/userfiles/files/26133676723.pdfIn PDF document text
    • http://heorungminhphat.com/luutru/files/97061679263.pdfIn PDF document text
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/16071154447fcf---84303409507.pdfIn PDF document text
    • https://batdongsandothanh.vn/luutru/files/71496285479.pdfIn PDF document text
    • https://gtsonline.nl/wp-content/plugins/super-forms/uploads/php/files/7pl6ou645mpp3shcsfh5kk56rc/lijetinugupo.pdfIn PDF document text
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16081d3234a96c---12907553024.pdfIn PDF document text
    • http://uniondeautoescuelas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610eddac6524c---wepikogutefimudavuzanede.pdfIn PDF document text
    • http://bobmeetin.com/media/galleries/files/78628569368.pdfIn PDF document text
    • http://softwarefactory.nl/images/file/13347753461.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_off0000e566.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE566 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fd7d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD7D 10860 bytes
SHA-256: a53b4fbc2efbed7671608c53e166d61f5d972dd16d056b3386acb1ffddd50ec0
font_02_sfnt_off00011683.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11683 17944 bytes
SHA-256: ea685e86215ba4a8faaa62e263e014f5a061732f1aa9a3ed0d33bab4da8aa469