Malicious PDF — malware analysis report

Static analysis result for SHA-256 1dad91628952bbc6…

MALICIOUS

PDF

100.7 KB Created: 2021-07-22 10:44:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 76cf3d6a73b0e3de00628d5a5d5ac077 SHA-1: 7989af93ada797a0cb4b7dfff2ca596eb5feb9d6 SHA-256: 1dad91628952bbc6657476cd183beffd467c8f37b8a9f6678613dd7294bb68ea
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identify it as a link farm hosted on compromised WordPress sites, with numerous distinct hosts and links. The presence of multiple PDF files hosted on these compromised sites suggests a campaign to distribute malicious documents, likely via phishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9877

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://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1609cfacbcb787---82146472611.pdf In PDF document text
    • http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a07059a88b2---befezikovop.pdfIn PDF document text
    • https://www.modianodesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e8ded24408---68491210328.pdfIn PDF document text
    • https://sahyadrisevasanstha.in/userfiles/file/jufajero.pdfIn PDF document text
    • https://mkting.com.co/wp-content/plugins/super-forms/uploads/php/files/b31af1e644f2c9c58e167622c7e84bac/60529050782.pdfIn PDF document text
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/16084caa126e2f---tejozusukizetinakibexizoj.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160944f8f3a655---jenefudexog.pdfIn PDF document text
    • https://www.ltgpartners.com/wp-content/plugins/super-forms/uploads/php/files/0b315f53d0ee528cb9eeb9549bc532f8/5604082084.pdfIn PDF document text
    • https://sdyh.gr/wp-content/plugins/super-forms/uploads/php/files/egtsto1k21bmmcc3bldr9n4ef5/33088140735.pdfIn PDF document text
    • http://www.canadavisaservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609cf1a560193---90398774663.pdfIn PDF document text
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098e57420567---46988639613.pdfIn PDF document text
    • https://mavismanagement.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c7777e171e9---fedepebolalexinuxuzoxapat.pdfIn PDF document text
    • http://www.patricktennis.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b431dea43eb---xebunuwom.pdfIn PDF document text
    • https://munord.com/wp-content/plugins/super-forms/uploads/php/files/eb990bfd88fa11bd780979522727d2ce/34098720780.pdfIn PDF document text
    • https://amenagementsoleil.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a7d6e54be8---dajana.pdfIn PDF document text
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/40305862c74cf6827c733e241f95d928/12416264122.pdfIn PDF document text
    • http://www.ibadirect.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a21e40eefa6---suviwuwosuvilemupap.pdfIn PDF document text
    • http://berkeleyhigh64.com/clients/9/99/99a482d4bd0dc5522cc24ea7f8204a07/File/44767880642.pdfIn PDF document text
    • https://areshin.ru/wp-content/plugins/super-forms/uploads/php/files/d9ce477edb71e74d47ac53554b8c2996/71239777439.pdfIn PDF document text
    • http://heilpraxis-pankow.de/wp-content/plugins/formcraft/file-upload/server/content/files/160bd57e66ac98---gaxibesifumibetipuj.pdfIn PDF document text
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f1a3ba07686---7205376773.pdfIn PDF document text
    • https://hmjrgoldhockey.org/wp-content/plugins/super-forms/uploads/php/files/1c3af73c264c1e8bc2d39f86e38f8cc5/refalut.pdfIn PDF document text
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160de1b256d238---85649333658.pdfIn PDF document text
    • http://bio86.fr/fichiers/15232642247.pdfIn PDF document text
    • https://awlights.com/wp-content/plugins/super-forms/uploads/php/files/59841d8d7e149244544dbb67e1e344e3/25521196071.pdfIn PDF document text
    • https://www.physioaktivkramer.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606efba9c2c2a---fetefisa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=physical+aspect+meaningPDF 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_off00012751.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12751 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00013f68.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13F68 10716 bytes
SHA-256: f413f1571aa938bb653cacf9191b899fbed752310625b6008478164be3d72485
font_02_sfnt_off000157da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x157DA 17448 bytes
SHA-256: 53a81dded2543c965b0da15285cb83d017314b61679e88e2927b750707cc6b2c