Malicious PDF — malware analysis report

Static analysis result for SHA-256 f9a3e237fea66144…

MALICIOUS

PDF

84.7 KB Created: 2021-07-07 09:16:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 35df9e746147fd07b9c1e041f3881921 SHA-1: 6664d50ff80b06aa4c7c5085d1120117e0742e83 SHA-256: f9a3e237fea66144f291cc88c2eb07b92fa2222d449ea8ef99fe2735ce5f616e
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple distinct hosts, many of which appear to be compromised CMS uploads. The embedded URLs and the nature of the heuristics strongly suggest an attempt to redirect users to malicious content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://avenue102.com/uploads/file/samafupegof.pdf In PDF document text
    • https://sipare.com.ar/wp-content/plugins/super-forms/uploads/php/files/2sj2o6mv0t4djiamqr1jitutth/nagukosumitebosipi.pdfIn PDF document text
    • https://www.indee-r.fr/wp-content/plugins/super-forms/uploads/php/files/e9a93fef78bc3475fc3b75ef67528839/zarudipalenezidasedofemo.pdfIn PDF document text
    • http://slp72.com/clients/7/7b/7b902bee17765b19ebdde6030f24742d/File/73270063428.pdfIn PDF document text
    • http://structurecreative.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d9a386a86fa---mimegozowiwupumepajuzolo.pdfIn PDF document text
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b1bce329cfb---21866336472.pdfIn PDF document text
    • http://pebyte.com/wp-content/plugins/super-forms/uploads/php/files/rhrh6a202eg27eeknpvol2m82b/jelafabamofejutar.pdfIn PDF document text
    • http://bridgesonthepark.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9938f15fcd---69986120680.pdfIn PDF document text
    • http://anhopphat.com/uploads/files/35027610805.pdfIn PDF document text
    • https://wecareprogram.org/images/file/ririvutodibi.pdfIn PDF document text
    • http://chagatea.ru/wp-content/plugins/super-forms/uploads/php/files/95b81fcc7b60405ce4e4714cc0ffe594/pubilopel.pdfIn PDF document text
    • https://bluetact.com/locktactyuma/userfiles/file/xexiralum.pdfIn PDF document text
    • http://www.britocunhaadvocacia.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/160826ed61e595---xegomuxitudaxevi.pdfIn PDF document text
    • http://bellezaeimagen.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160b43183e2d95---sekefokulog.pdfIn PDF document text
    • http://np-laser.com/upload_fck/file/2021-6-30/20210630134407279918.pdfIn PDF document text
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160d08657e6b9c---nopikezaledijadun.pdfIn PDF document text
    • https://udachi.co.th/wp-content/plugins/super-forms/uploads/php/files/oro1p2ci35n4rp2qosk2btrl9n/8603602348.pdfIn PDF document text
    • http://scissortailfarms.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099786f6c0b3---37892845623.pdfIn PDF document text
    • http://miyozenemeryville.com/uploads/files/wiropotojugenarixofe.pdfIn PDF document text
    • http://scissortailfarms.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aad7505a9d9---wokipamirisadi.pdfIn PDF document text
    • https://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fa73c3b920---95737927215.pdfIn PDF document text
    • https://cgeminfos.ma/upload/file/11945947481.pdfIn PDF document text
    • http://allegroescrow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e4a5ef6e37a---kepulukubikeguvonuravaz.pdfIn PDF document text
    • http://ehomeforeclosure.org/images/file/49871338188.pdfIn PDF document text
    • http://klinok-saintp.ru/files/rilipow.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=pdf+and+word+readerPDF 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_off0000ec25.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC25 16916 bytes
SHA-256: 06249152e30e7410d3c39223ae76fbe48e69884645a194e0b1e728efbc8a09db
font_01_sfnt_off000117ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117FF 10028 bytes
SHA-256: 7e8353833e829799a52031656a2e3c373e56eb0c9020c71637d2588c256a8743
font_02_sfnt_off00012e75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E75 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1