Malicious PDF — malware analysis report

Static analysis result for SHA-256 52e81aaa0cbcd32f…

MALICIOUS

PDF

74.7 KB Created: 2021-07-02 21:03:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: a8c0195181af5aac31ea42566690ec9d SHA-1: a2d9c1d7e1e002fa22a81fb3ce2bba6a2c3556e3 SHA-256: 52e81aaa0cbcd32f3c1d91912bb9ea7d07a0818d530234452262e0c851ed11a8
156 Risk Score

Malware Insights

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

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It functions as a link farm, with numerous URLs pointing to compromised WordPress sites and disposable domains, likely to lure users into phishing or malware downloads. The presence of multiple external URIs and link farm heuristics strongly suggests a phishing or distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9837

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://archism.ru/uplcv?utm_term=human+anatomy+for+artists+eliot+goldfinger+pdf PDF link annotation
    • https://pilotcenter.gr/wp-content/plugins/super-forms/uploads/php/files/dkhcg6ep392anvpnleamac06go/legumibexepoluwutegamo.pdfIn PDF document text
    • https://www.frankreich-ferien.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1607031749191a---nepisenubom.pdfIn PDF document text
    • https://robert-zauer.cz/userfiles/file/tiwidojuf.pdfIn PDF document text
    • http://1night2daytour.com/ckupload/files/63327982527.pdfIn PDF document text
    • http://bitite.lv/media/txt/122/file/wukemun.pdfIn PDF document text
    • http://angelcabrera.com/FCKfiles/file/30514825563.pdfIn PDF document text
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/efieooqglbrustaq9ei8qf8i7v/rapodakeliperepaligo.pdfIn PDF document text
    • http://furniture83.com/upload/files/pitixufav.pdfIn PDF document text
    • http://andrelandberg.com/userfiles/file/97248436575.pdfIn PDF document text
    • https://prana.video/wp-content/plugins/super-forms/uploads/php/files/ukgdm1pn86hi5oto6hdgkpmqvp/31329172229.pdfIn PDF document text
    • https://mfdesign.hu/files/file/2391965930.pdfIn PDF document text
    • https://swalaya.in/userfiles/file/38853681048.pdfIn PDF document text
    • https://www.cfo-search.com/wp-content/plugins/formcraft/file-upload/server/content/files/160855ba7cb7e6---12064418447.pdfIn PDF document text
    • http://appletechsolutions.com/userfiles/file/nagizotajavarosakukumij.pdfIn PDF document text
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16087d299dceea---wipawiwozo.pdfIn PDF document text
    • https://mikepromedia.com/wp-content/plugins/super-forms/uploads/php/files/kivkmsijq154lk8nmg0igie9v1/meleseti.pdfIn PDF document text
    • http://www.sealjet.mn/pictures/files/1943766210.pdfIn PDF document text
    • https://irisapp.cn/uploadfiles/fckeditor/20210523/file/16217842092404.pdfIn PDF document text
    • http://opalbiosciences.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086ca90c983d---19260970234.pdfIn PDF document text
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160d63a8017e76---vavatezubiwidad.pdfIn PDF document text
    • http://esoftland.com/userfiles/file/ronexeme.pdfIn PDF document text
    • http://meyanko.com/userfiles/file///78724769009.pdfIn PDF document text
    • http://kennyre.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d4233871257---mivonalupito.pdfIn PDF document text
    • http://www.ibadirect.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c96e993fbe7---87947622996.pdfIn PDF document text
    • http://czdashan.cn/uploadfile/file/2021062418480773499.pdfIn PDF document text
    • http://vizit-k.net/uploads/editor/files/lebobitomavunete.pdfIn PDF document text
    • http://dollreunion2020.com/clients/4/43/4392dc7a9e9236654a628da0af121bbb/File/72518567911.pdfIn PDF document text
    • 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_off0000be40.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBE40 11044 bytes
SHA-256: 7340f1a1660f9a0c1e573ca7c3772ab3e863db4593c5fc4ccec7f166eddee49e
font_01_sfnt_off0000d7b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7B7 17336 bytes
SHA-256: 3b0cf1f84486316631c1f7a54c6882b542beb7f93427fcfda2687117cb68dd82
font_02_sfnt_off00010338.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10338 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1