Malicious PDF — malware analysis report

Static analysis result for SHA-256 0f013b0a307e85f4…

MALICIOUS

PDF

77.6 KB Created: 2021-07-24 08:31:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: a3b11e2d04e8e946f6dc7c346d67a804 SHA-1: e8a8f97c0825d4bb5b7b381c8971d74cd8745c35 SHA-256: 0f013b0a307e85f4cd57fcf7f58c95cf6bd1818d427b29ff81deffb9afc26f92
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as malicious, including a high-confidence ML classifier and ClamAV detection. It functions as a link farm, containing numerous URLs pointing to compromised WordPress upload directories. These links likely serve as a distribution mechanism for phishing content or further malware. The presence of multiple links on potentially compromised sites suggests an attempt to obscure the true malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://www.mixedclass.com.au/wp-content/plugins/super-forms/uploads/php/files/k65tv205blvcfh2a3pj5jdmvr9/dekut.pdf In PDF document text
    • https://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/c55a2611917933766671966b5c0e4786/64624638032.pdfIn PDF document text
    • http://stpetersame.com/clients/9/91/91902b33218228c9a3691be2563b71f1/File/siguwetipedifat.pdfIn PDF document text
    • http://mfplus.ba/wp-content/plugins/formcraft/file-upload/server/content/files/1607fb5a689600---tavoni.pdfIn PDF document text
    • https://gccpay.net/wp-content/plugins/super-forms/uploads/php/files/12866cd49913c52c2aeca1917f43b2e0/18750947675.pdfIn PDF document text
    • http://ziepniekkalns.lv/wp-content/plugins/formcraft/file-upload/server/content/files/160bfccb60ab86---65428633576.pdfIn PDF document text
    • https://www.pietri-automobiles.com/wp-content/plugins/super-forms/uploads/php/files/bp4u5k3425uj1hp3sm3d0gckvc/fujedusixopogogekor.pdfIn PDF document text
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160abdb516b9b1---fezikipujovexavaw.pdfIn PDF document text
    • http://phenix-security.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607920f9cd975---ravoroponumiba.pdfIn PDF document text
    • https://schilderlesvakantie.nl/ckfinder/userfiles/files/tidafefurewivapafuvozilek.pdfIn PDF document text
    • http://posekatzahradu.cz/files/file/67202742299.pdfIn PDF document text
    • https://wecafephuket.com/wp-content/plugins/super-forms/uploads/php/files/odflm2rda4mpjq6cio7frudhup/15489734986.pdfIn PDF document text
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608119e81b337---35120590965.pdfIn PDF document text
    • http://fitnessklub-impuls.pl/uploads/assets/file/72218885494.pdfIn PDF document text
    • https://curvy.tw/upload/files/9489174393.pdfIn PDF document text
    • https://alarrabnews.com/images/content/content/file/98241087242.pdfIn PDF document text
    • https://tiklatakip.com/calisma2/files/uploads/89983925499.pdfIn PDF document text
    • http://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5ca5238db2---xabavijobe.pdfIn PDF document text
    • http://erbilsunhotel.com/wp-content/plugins/super-forms/uploads/php/files/4ki3qeid3gi4ed4edb8ej5jmr4/78532458993.pdfIn PDF document text
    • https://deltagroup.bg/uploads/file/36365182426.pdfIn PDF document text
    • http://hindel-relax.ch/ckfinder/userfiles/files/58826572960.pdfIn PDF document text
    • http://nuovojob.com/userfiles/files/50198556686.pdfIn PDF document text
    • http://alemotta.com/resources/original/file/86812221248.pdfIn PDF document text
    • http://walosports.cl/userfiles/file/67759274402.pdfIn PDF document text
    • http://m2m2design.com/userfiles/78300864955.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=ions+pogil+answer+key+chemistryPDF 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_off0000ce02.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE02 15932 bytes
SHA-256: 7d79c068e6eaeacea43d2171f8c9d33106f59ed2c41539623ced528c7a521b62
font_01_sfnt_off0000f6f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6F9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010f10.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F10 11064 bytes
SHA-256: 59ae8c78a941e814123ca5c5218fe366796702256e54e7f37ee713cca8974b13