Malicious PDF — malware analysis report

Static analysis result for SHA-256 7a09ccebb491d76f…

MALICIOUS

PDF

83.9 KB Created: 2021-06-25 12:03:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: f521ff0916f67b455af11ffc6e11d9b7 SHA-1: 7b7a9e25504ffdf0a92d843c2c9431b124d4611b SHA-256: 7a09ccebb491d76f32a4b3ddb629a2309842fd0c23c443d23594d01b539dc872
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent. The presence of multiple external URIs and link farm heuristics confirms the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://puertoestereo.com/wp-content/plugins/super-forms/uploads/php/files/q7id4lr6kt0hgoo2r8tevvgbst/30606863590.pdf In PDF document text
    • https://ehblending.com/wp-content/plugins/super-forms/uploads/php/files/baac1a6f7e6fff9ce5a3c810928f0eab/nexezosujunokovojidikokij.pdfIn PDF document text
    • https://tirthmobile.com/wp-content/plugins/super-forms/uploads/php/files/t3d894t8sjt8k4ogtr22q3qfng/tonimaxilevemoxazelunevil.pdfIn PDF document text
    • https://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/1608618c397377---67174794309.pdfIn PDF document text
    • https://engineeredrepinc.com/wp-content/plugins/super-forms/uploads/php/files/6b8497db38884cf952fdb4a31f8f92d5/wululujepopejojates.pdfIn PDF document text
    • http://www.airportlimofortlauderdale.net/wp-content/plugins/formcraft/file-upload/server/content/files/160af916ada84e---rovubanenunajasunibaj.pdfIn PDF document text
    • https://theemperorsoldclothes.co.uk/wp-content/plugins/super-forms/uploads/php/files/bicvifabo6v379set2rrsaagsi/fulola.pdfIn PDF document text
    • http://imi.vc/upload/files/kebulopegirekok.pdfIn PDF document text
    • https://vashadvokat82.ru/wp-content/plugins/super-forms/uploads/php/files/c23baca400d5481af77e9e6a75c33784/ledigifaxikoti.pdfIn PDF document text
    • http://iphysiology.ru/upload/damojowuvotitojuke.pdfIn PDF document text
    • http://www.awakohchang.com/image/upload/File/1377759976.pdfIn PDF document text
    • http://aliceinformaticasrl.com/user/pages/68762096039.pdfIn PDF document text
    • https://www.idahomedia.com/wp-content/plugins/super-forms/uploads/php/files/994d684068bfd6c11f22a2cfa7cbd31c/58880267944.pdfIn PDF document text
    • https://voziky-paletove.cz/mctree.cz/pictures/other/files/desobizudukotapujo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=clash+of+clans+mod+pc+downloadPDF 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_off0000e619.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE619 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fe2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE2B 17528 bytes
SHA-256: 79a923aaad8329d3ee190b85ed2ebdc5c9df14782a4cba89451c5940628bf0cc
font_02_sfnt_off00012b56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B56 10580 bytes
SHA-256: 031b3516a8f762afd86de6927d02061410e3e56649b4ac819ebd92d16e2f4502