Malicious PDF — malware analysis report

Static analysis result for SHA-256 c6544db28448a716…

MALICIOUS

PDF

94.9 KB Created: 2021-06-27 16:42:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 586ff0b518f76fb8ad7df909bdd627a6 SHA-1: 9d27d61bf66f049ebd7bf51ddce7d298587cc604 SHA-256: c6544db28448a716bc43305c9df306d9f3e272fedbbc074631b0d86e890d2873
156 Risk Score

Malware Insights

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

The file was detected by ClamAV as a Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. Heuristics reveal it functions as a link farm, directing users to multiple compromised WordPress upload storage locations and other unknown domains. The presence of numerous links on disposable hosting suggests an attempt to obscure the ultimate destination or distribute malicious content across various sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://estigotours.com/wp-content/plugins/super-forms/uploads/php/files/4a881e0dc5c178276564f85f6e155a54/15874257322.pdf
    • https://psg66.ru/admin/ckfinder/userfiles/files/34029221276.pdf
    • http://alituncer.com/userfiles/file/95387612995.pdf
    • https://gtsonline.nl/wp-content/plugins/super-forms/uploads/php/files/7ebpudmutni8m86qif1ebrv704/dugoresosewo.pdf
    • https://parquesanalbertohurtado.cl/ckfinder/userfiles/files/25781308526.pdf
    • http://carmakers.cz/userfiles/files/54538820714.pdf
    • http://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/160909def9b683---63120293031.pdf
    • http://www.jhannahs.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a16286a25a9---gejatopegelovaz.pdf
    • https://antoinepanau.com/wp-content/plugins/super-forms/uploads/php/files/fabaf0176c35196c01e3a11b798ef67b/6126090858.pdf
    • https://www.sir.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608295060da0a---nakiteridaf.pdf
    • http://kyanite.tv/userfiles/file/jekofedilesenibunajol.pdf
    • http://inewbus.com/wp-content/plugins/super-forms/uploads/php/files/9o5so25u7k8npklk5gdjusdkr1/xuxuzematogegedesojov.pdf
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160730d260e047---36191706144.pdf
    • http://marcobernini.it/userfiles/files/38506515068.pdf
    • https://thriveelearning.com/wp-content/plugins/super-forms/uploads/php/files/de085dcf742969e699fc1d23460f0c38/82897769406.pdf
    • http://frigotechreina.com/userfiles/files/5217604748.pdf
    • https://www.cr-sdc.org/wp-content/plugins/super-forms/uploads/php/files/eb9d33fa56b03309be597e14c24a5053/30845919314.pdf
    • http://www.1atlanticfunding.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9db007c1d---xefexolulebuwe.pdf
    • http://provia-events.de/pics/fotos/1/file/suworilisagerifubufebagu.pdf
    • http://hyperasp.net/userfiles/file/57636461719.pdf
    • http://veronicanealhome.com/wp-content/plugins/formcraft/file-upload/server/content/files/2/160d0a9ebb6f4e---pokoparevosamesujupiwe.pdf
    • https://lashmakerpro.it/wp-content/plugins/super-forms/uploads/php/files/2eke07cumvo3efuqbga76b8jn4/lujolezev.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=interesting+facts+about+numbats
    • 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_off0001104d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1104D 16792 bytes
font_01_sfnt_off00012864.bin
492f3ba77a84319de33347daff777f76f68f3e3004a82c2a9cc594f5787315c2
pdf-font-stream PDF embedded font (sfnt) at offset 0x12864 10824 bytes
font_02_sfnt_off00014165.bin
dfac07ffdc7f811c965810e89644ce9da4b0d584d5dc8a0f0f7148757b1a0272
pdf-font-stream PDF embedded font (sfnt) at offset 0x14165 17196 bytes