Malicious PDF — malware analysis report

Static analysis result for SHA-256 c8b3d7cf2242f25c…

MALICIOUS

PDF

67.7 KB Created: 2021-09-20 16:27:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: fd5a88ceddadfecb1c830db9f363c327 SHA-1: c0d1e99bf2536d2b9a49155567b59a54555f0f86 SHA-256: c8b3d7cf2242f25c29b7a7686ecc08fe5701cd028bc2ed0ecbbc5ead988aed20
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains embedded JavaScript and is flagged by heuristics as an image-only document with an action trigger, typical of a phishing lure. It also functions as a link farm on disposable hosting, directing users to external URLs. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to a phishing site or download further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 67 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://garglob.ru/uplcv?utm_term=novel+my+lecturer+is+my+husband+pdf PDF link annotation
    • http://www.yt333.com/userfiles/20210911/file/1631324345.pdfIn PDF document text
    • https://es21sys.com/userfiles/file/wuvuxilukigodarawovoseko.pdfIn PDF document text
    • https://aymexco.ro/ckfinder/userfiles/files/9737360501.pdfIn PDF document text
    • https://wcfkenzi.com/ckfinder/userfiles/files/25033560954.pdfIn PDF document text
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613d56f35d021---65562539698.pdfIn PDF document text
    • http://jinistudy.com/_UploadFile/Images/file/bunesejatazidugavirerad.pdfIn PDF document text
    • http://studiorapizza.it/userfiles/files/57344292657.pdfIn PDF document text
    • http://esoftland.com/userfiles/file/xurukabolepir.pdfIn PDF document text
    • https://valubil.com/public/uploads/cms_file/cms_files/sanukagewonejevoja.pdfIn PDF document text
    • https://oriental-kitchens.com/userfiles/files/nerijago.pdfIn PDF document text
    • http://pogotowienaukowe.com/Upload/file/54017146971.pdfIn PDF document text
    • https://www.educazionesessuale-scuola.ch/ck/ckfinder/userfiles/files/11524489369.pdfIn PDF document text
    • http://abwingscolley.com/uploads/files/2782234070.pdfIn PDF document text
    • http://elma-itc.ru/!upload/files/1556192583.pdfIn PDF document text
    • http://ztkammer.at/uploads/file/15000906375.pdfIn PDF document text
    • http://portofmiamitunnel.com/system/js/back/ckfinder/userfiles/files/41390110951.pdfIn PDF document text
    • https://transilvaniafishing.ro/app/webroot/files/userfiles/files/bepipowigeragivi.pdfIn PDF document text
    • http://sp2wronki.pl/fotki/fotki/file/fabowikunazoxab.pdfIn PDF document text
    • https://lionkingbali.com/uploads/file/22549442236.pdfIn PDF document text
    • http://lmalaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/25040037456.pdfIn PDF document text
    • http://cnkls.com/userfiles/file/1631615889.pdfIn PDF document text
    • https://perfectsextherapy.com/public_html/userfiles/file/9591370867.pdfIn PDF document text
    • https://pellevah.com/upload/files/71913437048.pdfIn PDF document text
    • 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_off0000acdd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xACDD 13852 bytes
SHA-256: eb8251649a790cf77685256f0b7d3223e546feba0584999727c62d2bd0b794d4
font_01_sfnt_off0000cf09.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF09 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e720.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE720 11284 bytes
SHA-256: 5ec41783d367af422caea64c66a5ecae9cfd224bb472d442b048207367a80143