Malicious PDF — malware analysis report

Static analysis result for SHA-256 91dc1f15951f1fef…

MALICIOUS

PDF

106.4 KB Created: 2021-07-31 08:53:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: aad85466e6a8e99104d7b38e533b7b99 SHA-1: 4597292e6a074fe3fae3f61e1b9f97a307d2f8a7 SHA-256: 91dc1f15951f1fef4b5276bf598470a2218c30ccfdd1517c9640b7ee36648de7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains numerous links pointing to various websites, many of which appear to be compromised WordPress installations or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or SEO spam. The presence of multiple external URIs and link farms suggests an attempt to distribute malicious content or manipulate search engine rankings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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 http://businessplan-capalpha.fr/mbp/upload/images/images/upload/ckfinder/bewotusotitaxemuzawan.pdf In PDF document text
    • https://www.sussexweddingservices.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1609b67aa46a9e---4406317827.pdfIn PDF document text
    • https://www.guestquesttravelmedia.com/wp-content/plugins/super-forms/uploads/php/files/2p8auf8a5shpuhhtb1cvr10l4j/sogekunetofuwa.pdfIn PDF document text
    • http://forumcutuca.com/ckfinder/userfiles/files/babazuloferorupafuwa.pdfIn PDF document text
    • http://kojeneckezbozi.eu/userfiles/file/31384027159.pdfIn PDF document text
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16098b3d918b94---16108698951.pdfIn PDF document text
    • https://sharidendesignasphalt.com/wp-content/plugins/super-forms/uploads/php/files/08291afeb4d559b3916c37beb5d32b85/pajanu.pdfIn PDF document text
    • https://yidinfo.net/wp-content/plugins/super-forms/uploads/php/files/spsif7pbggqmmblfhaf64gsqdb/pipogesetezewupor.pdfIn PDF document text
    • https://noble-worldwide.com/wp-content/plugins/super-forms/uploads/php/files/f01d4eeb87eab732f1a3de97e844d987/40549502962.pdfIn PDF document text
    • http://ofitecnic.es/files.ofitecnic/fck_up/file/manujol.pdfIn PDF document text
    • http://www.atrium-tuiles.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c566cad8fe---62612850911.pdfIn PDF document text
    • http://thayloilocnuoctaihanoi.net/upload/files/garewafobakururikefubakek.pdfIn PDF document text
    • https://alatheir.com/atheirwsfiles/file/kimulekilojigelubew.pdfIn PDF document text
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/160d411dc05850---84989571907.pdfIn PDF document text
    • http://erkerlaender.de/wp-content/plugins/formcraft/file-upload/server/content/files/160791b866ee75---91811495870.pdfIn PDF document text
    • http://parkwestresidences.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aac99eb2631---73347534371.pdfIn PDF document text
    • https://alasclub.gr/neuro/ckfinder/userfiles/files/kebawezup.pdfIn PDF document text
    • http://brcassociati.com/userfiles/files/1406164864.pdfIn PDF document text
    • http://martonaroniskola.net/userfiles/file/95530638468.pdfIn PDF document text
    • http://www.sudaff.com/pics/file/xixudusinovusuxaz.pdfIn PDF document text
    • http://sbs-group.co/userfiles/files/zoxulovodefo.pdfIn PDF document text
    • http://iwish-cosmetics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e1de9d9d8b4---buzesububasuluzupi.pdfIn PDF document text
    • http://xn----8sbxab3abskk3a2j.xn--p1ai/media/file/79395794254.pdfIn PDF document text
    • https://www.booster-p.com/wp-content/plugins/formcraft/file-upload/server/content/files/160893e3127416---43706866289.pdfIn PDF document text
    • https://plumcourse.com/wp-content/plugins/super-forms/uploads/php/files/e16894d71266767bd8513fae3b17cf7f/43624963340.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=how+to+write+a+job+reference+letterPDF link annotation
    • 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_off000139ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x139CE 10508 bytes
SHA-256: 01b695a99ef8a411a3a0708dc352d83eb174e013ecb1fd7587f241fd60a27106
font_01_sfnt_off000151cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x151CD 17804 bytes
SHA-256: 3395ab194c35f0fbfc29c38bc246cf3c5935209e0dc78aa8bc186e27c06a0a68
font_02_sfnt_off00018060.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18060 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1