Malicious PDF — malware analysis report

Static analysis result for SHA-256 25746db525be1310…

MALICIOUS

PDF

76.2 KB Created: 2021-10-06 10:00:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 5b4b81fd2f33d2257aa37f38bb1f906d SHA-1: 997205bd8c833f6fe08e4a8d1e333dca2ffd1a8c SHA-256: 25746db525be13101d2a0e42bf1b21d75302526f1ef0e691c9c8ecf0d57d87fa
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to disposable domains and are structured as a link farm, indicating a probable attempt to redirect users to malicious sites. While no scripts were explicitly extracted, the PDF structure and heuristic firings suggest it's designed to exploit users through deceptive links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://restavratorstvo.com/ckfinder/userfiles/files/menomapu.pdf In PDF document text
    • https://hahapediatric.com/uploads/files/202109050954224465.pdfIn PDF document text
    • https://rh4-h1tapi-turbo.com/contents/files/kagota.pdfIn PDF document text
    • http://cowmoo.org/ckfinder/userfiles/files/pegewizet.pdfIn PDF document text
    • http://farmaciafoglia.eu/userfiles/files/nirife.pdfIn PDF document text
    • http://vivo-mebel.ru/upload/file/fatagudilut.pdfIn PDF document text
    • http://esebtekstil.com/resimler/files/rajanogovetikax.pdfIn PDF document text
    • http://diamant-x.sk/UserFiles/file/5751552961.pdfIn PDF document text
    • http://pelesiuvalymas.lt/i/File/purevumexutevitorivefoto.pdfIn PDF document text
    • http://www.ezmoving.com/file/dadufeferewekev.pdfIn PDF document text
    • http://snieznik.pl/userfiles/file/miwanamolikizefifuparu.pdfIn PDF document text
    • https://wholisticvibrations.com/wp-content/plugins/super-forms/uploads/php/files/b4cac023482f049dea9be09c47e011b6/xajaxewimalawexixa.pdfIn PDF document text
    • http://refpecsbelvaros.hu/kepek/files/57762415482.pdfIn PDF document text
    • http://apisicul.com/userfiles/files/66185332268.pdfIn PDF document text
    • http://bloodfaces.de/attachment/file/16884751960.pdfIn PDF document text
    • http://konberdbio.com/upload/files/1321440881.pdfIn PDF document text
    • https://moolans.com/uploads/files/83687105289.pdfIn PDF document text
    • http://alliance-ic.ru/uploads/file/37818189633.pdfIn PDF document text
    • https://stdtekstil.com/upload/ckfinder/files/xinukukoregotigonoj.pdfIn PDF document text
    • http://violetstudio.in/userfiles/file/sufovafevulor.pdfIn PDF document text
    • http://travel-door.com/userfiles/file/60019282741.pdfIn PDF document text
    • http://kuhomania.ru/ckfinder/userfiles/files/49670448658.pdfIn PDF document text
    • http://titadoorbinhduong.com/upload/files/27504115.pdfIn PDF document text
    • https://oxi-dental.ro/imagini_ws/didajesusukibej.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=the+plant+cell+quiz+answersPDF 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_off0000c1ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC1AD 18112 bytes
SHA-256: 6c0847bc38b0e5f893afc53e134e7fff206d3b9797eea8ffe599fbdd4bc603ff
font_01_sfnt_off0000f0d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0D1 10708 bytes
SHA-256: 57e1c95ec8b971be0272dd3bb445ea036dccc56a9c66e5354fda176eba978dd8
font_02_sfnt_off00010970.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10970 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1