Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1d36cef772f2194…

MALICIOUS

PDF

76.5 KB Created: 2021-09-06 01:57:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 89f14692ac59eed6fcdcba21b03852eb SHA-1: b776812c1bbca000b6f9d21cac4a18b7f0e20d60 SHA-256: a1d36cef772f2194c36b6836537cbdd7f47f9b0a8f55a3c784290f6faf8e9537
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by a machine learning classifier and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to various websites, including those hosted on compromised WordPress installations. The presence of multiple links and the use of UTM parameters suggest an attempt to lure users to potentially malicious content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://leo.tw/upload/ckeditor/files/39002238852.pdf In PDF document text
    • http://space-edge.com/upload/files/rafaxidavowas.pdfIn PDF document text
    • https://www.freshstartdigitalmarketing.com/wp-content/plugins/super-forms/uploads/php/files/edb6afb1d08b0192ea8c14b2815c2c29/dubuvovukisujogitu.pdfIn PDF document text
    • https://marupyara.com/fotos/userfiles/file/87071603703.pdfIn PDF document text
    • http://brixtontaxi.com/survey/userfiles/files/63251670530.pdfIn PDF document text
    • http://pawsandtiaras.com/ckfinder/userfiles/files/6739667849.pdfIn PDF document text
    • http://grupomarsamo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f87f9652860---jonarufivajowalemuti.pdfIn PDF document text
    • http://www.casasemio.com.br/ckfinder/userfiles/files/78291984606.pdfIn PDF document text
    • http://crm333.com/documentos/file/fozijuwubujipad.pdfIn PDF document text
    • https://amadesafar.ir/basefile/amadesafarir/files/sizijinag.pdfIn PDF document text
    • https://vashadvokat82.ru/wp-content/plugins/super-forms/uploads/php/files/1387de2c2ed5c82f0377f73676ecbee8/xowurosotifuvomuzogikot.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/jijidexofir.pdfIn PDF document text
    • https://alarouba.com/ckfinder/userfiles/files/19608430984.pdfIn PDF document text
    • http://grafichesirio.com/userfiles/files/kejitobevixavevutine.pdfIn PDF document text
    • https://burlingame.com/wysiwygfiles/file/valofonukom.pdfIn PDF document text
    • https://dolnoslaskialarmsmogowy.pl/imgturysta/files/pitaletireraj.pdfIn PDF document text
    • http://inezorviskids.com/clients/37546/File/40528104027.pdfIn PDF document text
    • http://www.marcelasemper.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b3aae66aae---83669185166.pdfIn PDF document text
    • http://botosani.ro/img/uploads/file/27965180344.pdfIn PDF document text
    • http://fasson.vip/images/editor/files/89161523350.pdfIn PDF document text
    • https://iguanapools.com.au/wp-content/plugins/super-forms/uploads/php/files/f8esf9se68mjeeaif6u5o2o4n7/reruzaforuvesit.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=electrical+engineering+multiple+choice+question+and+answer+pdfPDF 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_off0000c6f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6F6 11384 bytes
SHA-256: 0ddb30d8ed392d65598d6d307a48ded3efa32c1443a5d81f85e5e0dafc76141a
font_01_sfnt_off0000e11a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE11A 16796 bytes
SHA-256: eef2a3938e76874d434fe37bc3d9758ded6e505d291b79ccb21bacce6763b692
font_02_sfnt_off00010c06.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C06 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1