Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3d558f2ba4ec848…

MALICIOUS

PDF

71.0 KB Created: 2021-09-13 21:37:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: e6264e943e68bbd081c2b1d64b7941b0 SHA-1: f06b008c41a1abe36ed5de4c2ed16fa4f6db0e05 SHA-256: a3d558f2ba4ec848acc9dc9411d795a8278acd8e7860a65880f31383ac8f9834
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, suggesting a link farm designed to distribute malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware delivery. No scripts were extracted, but the structure and URL patterns are indicative of a downloader or phishing lure.

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://smidgel.ru/uplcv?utm_term=all+the+8+planets+in+order PDF link annotation
    • http://rheumatology.institute/upload/content/file/palebo.pdfIn PDF document text
    • http://tverzhilservis.ru/foktver.ru/ckfinder/userfiles/files/60542892691.pdfIn PDF document text
    • http://apnschool.in/singhania/downloads/file/tumimobijonabezojekasiv.pdfIn PDF document text
    • https://ganport.pl/userfiles/file/mixijiriluwawutodi.pdfIn PDF document text
    • http://www.majoriscambio.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613b94927c5b9---97014763179.pdfIn PDF document text
    • http://zhuoer.ltd/userfiles/file/47661338642.pdfIn PDF document text
    • https://broadstripe.com/wp-content/plugins/super-forms/uploads/php/files/097d499f10d73a6bdf91e97f908d04bc/35602124196.pdfIn PDF document text
    • http://industrialdevices.in/uploads/kilizinixavafuxeje.pdfIn PDF document text
    • http://maxitelt.no/wp-content/plugins/formcraft/file-upload/server/content/files/1613eb37422312---tobivej.pdfIn PDF document text
    • http://www.louisefarmersmith.com/admin/ckeditor/ckfinder/userfiles/files/sikigagososaseruri.pdfIn PDF document text
    • https://goodnest.info/tctt/sites/aaa/file/fefifu.pdfIn PDF document text
    • http://xlpe.net/Images_upload/files/14641536057.pdfIn PDF document text
    • https://4of100churchstreet.com/assets/media/files/xaguwo.pdfIn PDF document text
    • https://sowlindia.com/userfiles/file/77968398748.pdfIn PDF document text
    • https://o2opr.co/userfiles/files/tizegozomatofeme.pdfIn PDF document text
    • https://iskoruma.com/upload/ckfinder/files/38251768729.pdfIn PDF document text
    • http://mauchlineware.com/html/chapelstreet/web/userfiles/files/lobevoxiloviriso.pdfIn PDF document text
    • https://pemaboutiquehotel.com/assets/userfiles/files/84632314526.pdfIn PDF document text
    • http://hrdiborice.cz/erucom1/files/files/regosi.pdfIn PDF document text
    • http://hstairan.com/FCKeditor/editor/filemanager/connectors/php/userfiles/file/rafazuwijenotufede.pdfIn PDF document text
    • http://mynotary.ca/sites/all/sites/mynotary.ca/files/nosiliwidololuronabomag.pdfIn PDF document text
    • http://playeasypiano.com/resources/fck_images/77108916006.pdfIn PDF document text
    • https://trichynext.com/wp-content/plugins/super-forms/uploads/php/files/64abba35439d441e25fcfee6ec316fee/83785374811.pdfIn PDF document text
    • https://xn--b8qxb801j.tw/upload/files/65224709206.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_off0000b71b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB71B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cf2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF2D 15360 bytes
SHA-256: 4689be4a0d54524ff7c77852d66c9a315c653adca52524a6f0ed95489c534f18
font_02_sfnt_off0000f64f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF64F 10680 bytes
SHA-256: aad25f869b4cabaf52d8e2fd0fad5c036e3871a73a6f39051aea6ad80d6d13dd