Malicious PDF — malware analysis report

Static analysis result for SHA-256 d28db9a5d9752b65…

MALICIOUS

PDF

90.0 KB Created: 2021-08-01 01:53:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4612fa225aea6e15c1710b665866a311 SHA-1: f8594a7b7696dc108fa4650caf32720b6da4c8c7 SHA-256: d28db9a5d9752b6596802d6921dbc4759a84952fde023ddc17028ca710a95de8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains a link farm with numerous URLs pointing to various domains, many of which are hosted on disposable infrastructure or compromised CMS uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or redirection to malware. No scripts were extracted, and the document body was unreadable, but the heuristic firings are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://firanywiktoria.pl/uploads/editor/file/34650935978.pdf
    • http://annandale1963.com/clients/69704/File/sonerit.pdf
    • http://efuegypt.org/userfiles/file/lopedowapuje.pdf
    • http://www.ibadirect.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad3fe7be695---40868877331.pdf
    • http://pogotowienaukowe.com/Upload/file/42208064237.pdf
    • http://smflow.in/admin/uploads/file/52088685990.pdf
    • https://businessincasey.com.au/application/third_party/ckfinder/userfiles/files/bisalakuxuxuxagawuwedinu.pdf
    • https://akemi.ro/hirek/file/58300818121.pdf
    • http://www.britocunhaadvocacia.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/160c0ef7ca9fa8---16581665757.pdf
    • http://eurekaloggers1970.com/clients/a/a4/a4917853023b9a70bc4506ca58f09c65/File/vorinapesewok.pdf
    • http://namadagaskare.ru/ckfinder/userfiles/files/98232684561.pdf
    • http://bioident.pl/photos_fck/file/naxukerisejibuduzu.pdf
    • https://lightupalife.org.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608132ea0b9c1---10718710908.pdf
    • http://slowjamsundays.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074d844ee7e4---39898143621.pdf
    • https://candbco.com/ckfinder/userfiles/files/jarizi.pdf
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/3gnrl6q7uacneubrar43kng1j4/woxisofupikukitutude.pdf
    • http://bluekeydigital.com/images/pic/file/8713543367.pdf
    • http://www.fsnn.se/wp-content/plugins/formcraft/file-upload/server/content/files/1607911496fa6a---dukijajaberobomilijes.pdf
    • http://driver-jazda.pl/upload/file/74362025452.pdf
    • http://matchedtubes.de/userfiles/file/45306790271.pdf
    • http://turagent007.ru/userfiles/file/26459340057.pdf
    • http://lussoleathertiles.com/test4/EDITOR/example/v2/userfiles/file/mevusujuvatusafetowowe.pdf
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/16072e2db6679f---66747648849.pdf
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160f48a661003e---12751195626.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=celebrate+recovery+step+study+guidelines
    • https://tes-sys.com/uploads/ckfinder/files/20210705/16254152332346.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_off0000f791.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF791 16792 bytes
font_01_sfnt_off00010fa8.bin
a39ecc0168b5595925efc07f916ab0872ab285a4b5d282db9f8d83828d3e02aa
pdf-font-stream PDF embedded font (sfnt) at offset 0x10FA8 11140 bytes
font_02_sfnt_off0001296a.bin
88febe50498b502b78cd1dafef58eee4f1cb440fc0dd9d5d59a8d10e06a689a6
pdf-font-stream PDF embedded font (sfnt) at offset 0x1296A 18132 bytes