Malicious PDF — malware analysis report

Static analysis result for SHA-256 878cdf86c7d947f7…

MALICIOUS

PDF

87.2 KB Created: 2021-06-26 09:15:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8947efcdd3bf0c20f024f3f66e48d3d0 SHA-1: a3447a218b4cd8d2f70cfec372781fd3f16f609a SHA-256: 878cdf86c7d947f7671f462c2db688f2081ca4e92c9223a6f041fb99cc8428b6
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised WordPress sites, indicating it functions as a link farm. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. The presence of external URIs and compromised CMS upload links reinforces this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://ketchas.ru/uplcv?utm_term=procerus+muscle+function
    • https://macleanpinesdrivingschool.com.au/wp-content/plugins/super-forms/uploads/php/files/ffaecb015aeb1bd3fb60dfbedbdd76d3/rapamedupita.pdf
    • http://lalitas-thaimassage-spa.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609efb8038e3c---69314234670.pdf
    • https://provisionsinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0e499468ca---54050952901.pdf
    • https://communeouchamps.fr/userfiles/file/gikezewelusa.pdf
    • http://atthaya.com/file_media/file_image/file/zimugakowo.pdf
    • https://www.dekleinewerf.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609fd238d7921---28291384970.pdf
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/1607ecdf25312b---manipikagaronezixegiw.pdf
    • http://dongphuctqueen.com/upload/files/totoz.pdf
    • https://michaels-limo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b4d11935386---85768562665.pdf
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160c759dc68334---14822281201.pdf
    • https://www.capitalroofingct.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086f13e1f06e---parugufotafavad.pdf
    • http://capmar.eu/userfiles/file/roxupadamasorazazoda.pdf
    • http://birons.net/wp-content/plugins/super-forms/uploads/php/files/5f27ffaebf69212af3562d312a994493/25490021490.pdf
    • http://phenix-security.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607e9cab7a2b3---fonegu.pdf
    • http://orrizon.ru/images/file/sibedotafi.pdf
    • https://www.couleurs-et-jardin.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1606f1d3bd9d7f---pumotosudagiboniwejoxuse.pdf
    • https://www.cukoyem.com.tr/wp-content/plugins/super-forms/uploads/php/files/1pvgl9v5fllu6icd2bnn9bgdd4/32152022939.pdf
    • http://training-solutions.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16070b8d281cab---34327684430.pdf
    • http://investin-khj.ir/ckfinder/userfiles/files/36846755582.pdf
    • http://www.champcaregivers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160821d74bee17---pusaxuzumabukefanosijora.pdf
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/qtlecfmge4ffvdvdr6c6kvi9m7/gixituromuzipakavijud.pdf
    • https://www.lokalesichtbarkeit.de/wp-content/plugins/super-forms/uploads/php/files/qfqmf6g4b49b8n0qodivopipcl/nowavuvikejatuxu.pdf
    • https://alkhairi.co.uk/wp-content/plugins/super-forms/uploads/php/files/ec052b12909cbdef1aa739d22df275a7/susuposoxajipa.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f31a.bin
b940c91b0901290f1fecdcfbe3d388ef24526956d140af3adc61218459f5e06d
pdf-font-stream PDF embedded font (sfnt) at offset 0xF31A 10436 bytes
font_01_sfnt_off00010abd.bin
e1a1e896efc5132f4f2b66049adad6a6fc3525777e29d9c3da2a44f66ccc8657
pdf-font-stream PDF embedded font (sfnt) at offset 0x10ABD 16644 bytes
font_02_sfnt_off00013606.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13606 16792 bytes