Malicious PDF — malware analysis report

Static analysis result for SHA-256 c184861e8975f161…

MALICIOUS

PDF

87.1 KB Created: 2021-06-26 18:45:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 0364f3da2d2983c9d1cfb76a304f043c SHA-1: 90ddc9642dd120910ed950d313886deb776172ef SHA-256: c184861e8975f1611e098e26c4791d829e771b4296b6701bcbc85f0f23430bd8
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress upload directories, indicating a link farm designed to redirect users. ClamAV and ML classifiers flagged this PDF as malicious, specifically as a phishing trojan. The presence of multiple external URIs and a link farm heuristic strongly suggests an attempt to lure users to external, potentially malicious, content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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 http://amtusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bbe78a88fc0---13071747259.pdf In PDF document text
    • https://connect.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/ece10ae107441692356bfcfec199c678/jorofobuloj.pdfIn PDF document text
    • https://gtsonline.nl/wp-content/plugins/super-forms/uploads/php/files/dnp76m7vfagq47mm3g3djfu12f/26352352217.pdfIn PDF document text
    • https://samiznojmo.cz/wp-content/plugins/super-forms/uploads/php/files/39d681bd3bd87cd4c2c3ac5aad4386e7/pejixuvufo.pdfIn PDF document text
    • https://ajwatravel.com/wheelmarine/userfiles/file/baxunuxefejinewidopevom.pdfIn PDF document text
    • http://www.canadiantreasurer.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c9829c1887---lawutotuxawulezag.pdfIn PDF document text
    • https://anfauglir.com/images/file/sexopujol.pdfIn PDF document text
    • https://sckstone.com/wp-content/plugins/super-forms/uploads/php/files/742c183769186f638f2e28ba458c6b16/26476735519.pdfIn PDF document text
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/a395337cd8a0c95d48d14ac437440dad/gevuremaw.pdfIn PDF document text
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160bce737b78d9---14964127568.pdfIn PDF document text
    • https://diversifiedhumansolutions.com/wp-content/plugins/super-forms/uploads/php/files/5ce7b83001bdae51f6eed2aebb65f9cc/3103612661.pdfIn PDF document text
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/160889888196cf---94528263776.pdfIn PDF document text
    • http://www.afamaresme.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607b73a2e3be7---dogiwufov.pdfIn PDF document text
    • http://k1a.ru/images/files/file/tegopomabefipamerosijeka.pdfIn PDF document text
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608532f09ef03---67130170811.pdfIn PDF document text
    • https://takeorders.online/wp-content/plugins/super-forms/uploads/php/files/gmg9kvvbn8uk0etqpu7u67cqvm/15334925039.pdfIn PDF document text
    • http://endustriyelkiralama.com/wp-content/plugins/super-forms/uploads/php/files/kv9ud3e8rkcnibq991ctfqqjqg/pamudutotezutugafafadonoz.pdfIn PDF document text
    • http://schooldistrictservices.com/clients/f/f6/f6ab1571d2cdf5e569af7b76e288b17c/File/porujubupodadogejorar.pdfIn PDF document text
    • http://call.ae/wp-content/plugins/formcraft/file-upload/server/content/files/160768432ecbef---givilegane.pdfIn PDF document text
    • https://empylean.com/wp-content/plugins/super-forms/uploads/php/files/vf11u2ujdpbl58m3od71edf69u/gudunesipagaj.pdfIn PDF document text
    • https://mebelpozakazu.ru/wp-content/plugins/super-forms/uploads/php/files/97573bafe7d4425022a2d31414b11650/12752209782.pdfIn PDF document text
    • https://propbrains.com/wp-content/plugins/super-forms/uploads/php/files/e53hm14ob12gsjv9nrdljjiek3/nejipeju.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=the+queen+on+britain%27s+got+talentPDF 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_off0000f04c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF04C 17516 bytes
SHA-256: 575f9cd7bbad7faef8611ac98d495de2d2974aff824075daee3d32ab8c5f580d
font_01_sfnt_off00011ec2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EC2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000136d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x136D9 10772 bytes
SHA-256: 3df19e3b0ad96eff9ee6b2525de47ac15316fb28a4ed2c41734fdd6692bf3e95