Malicious PDF — malware analysis report

Static analysis result for SHA-256 fcd85c134da5b5de…

MALICIOUS

PDF

86.0 KB Created: 2021-07-13 19:36:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 30a02ba91558d95a4f087470b333a40f SHA-1: 461bda25edba80d84e3b220915700361963bef27 SHA-256: fcd85c134da5b5de598e6bad83842bcc47cc6b8e4e278d2172bccebbcb24a35d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, presenting numerous URLs that point to compromised WordPress upload storage and other disposable hosting sites. The presence of embedded URLs and the nature of the heuristic firings suggest this PDF is designed to lure users to external, potentially malicious, content.

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://cructi.ru/uplcv?utm_term=how+to+attach+a+pdf+to+an+email+in+outlook
    • https://samowar.ch/upload/file/17808202653.pdf
    • https://ost-fogging.com/upload/files/80395578170.pdf
    • https://www.focus.mu/wp-content/plugins/super-forms/uploads/php/files/b717115095939881a6c672f843fd119d/vatekukukadarezeditosa.pdf
    • http://alsumiri.net/wp-content/plugins/super-forms/uploads/php/files/af76a619d8d374c71f17107bb8496028/1043636680.pdf
    • http://cesnek-vysocina.cz/UserFiles/File/vevovepapofegu.pdf
    • http://spreewaldatelier.de/img/editor/file/9632956025.pdf
    • https://lea-inc.com/wp-content/plugins/super-forms/uploads/php/files/54780c63beb6d95311ea1a705fd51210/19904727201.pdf
    • http://aokisuper.com/ckfinder/userfiles/files/mujel.pdf
    • https://deewo.de/wp-content/plugins/formcraft/file-upload/server/content/files/16096a981b426e---81092269362.pdf
    • https://realwebguys.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dcddf29ff3c---batakanaditisinojexemex.pdf
    • http://lynhuagiasi.com/Images_upload/files/43470671588.pdf
    • https://faresaldabbous.com/uploads/files/99561281003.pdf
    • https://www.llgnjinc.com/wp-content/plugins/super-forms/uploads/php/files/5e995d4249ff116ce5d605376079028e/93121742234.pdf
    • https://suadienlanhhanoi.net/upload/files/993647074.pdf
    • http://hainescentreasia.com/images/file/65439775496.pdf
    • https://g3az.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ace5499d6b---46310707072.pdf
    • http://ahcxdq.com/uploads/file/011429358488.pdf
    • https://cspdental.com/wp-content/plugins/super-forms/uploads/php/files/78a3ff895716e650232807bdd098acd6/52369025364.pdf
    • http://windcampus.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a623c96efd---xisiviwijobigumipoguzure.pdf
    • https://advik.net/userfiles/file/65287191581.pdf
    • https://imagebeaute.fr/userfiles/file/meluwamazafiwegudi.pdf
    • https://floridainvestment.cz/files/file/wetafosapitawef.pdf
    • https://comodee.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c272b16a5f5---19909770098.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_off0000ed21.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xED21 16792 bytes
font_01_sfnt_off00010533.bin
20468cd953215ecec71af4c1cf50a600a3b087367347fa51f18ebe2f323e4c88
pdf-font-stream PDF embedded font (sfnt) at offset 0x10533 17048 bytes
font_02_sfnt_off000131b1.bin
21ed41467cbd181c1e3d95741e66a35df7d2565597c26cba4744a85c7cf781ae
pdf-font-stream PDF embedded font (sfnt) at offset 0x131B1 10884 bytes