Malicious PDF — malware analysis report

Static analysis result for SHA-256 50a837f3c721adf3…

MALICIOUS

PDF

90.2 KB Created: 2021-07-26 08:41:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 44b4acb7afc622fe87072e2be37c910d SHA-1: f7288c21689dedee5ca1cfba53cf56ec11228ed3 SHA-256: 50a837f3c721adf3206423f907b98762cde9829e83a4639b2ac66f3b791a3f5f
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, directing users to multiple external URLs, some of which are hosted on compromised CMS platforms or disposable domains. This suggests a phishing or SEO poisoning attack pattern, aiming to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9866

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://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076c2b76268f---72022021275.pdf
    • http://yorkiematch.com/clients/6/65/653dc45b8f6063886304ac4260dbb99c/File/64733041700.pdf
    • http://bassbasement.org/userfiles/file/40533490141.pdf
    • https://www.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160840bf342e45---84558857330.pdf
    • http://kxzyjy.com/CKEdit/upload/files/42682454198.pdf
    • https://www.ogblfrontaliers.fr/wp-content/plugins/super-forms/uploads/php/files/hp3bmufjq61t9rsdi6etc4d7bb/jetesogabipegus.pdf
    • https://www.chortho.co.uk/wp-content/plugins/super-forms/uploads/php/files/e5g8agrddf181rlb8k8520efu1/75119817074.pdf
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160e01904c2f6a---tiwaxuzizebuzi.pdf
    • http://dodici12.ru/wp-content/plugins/super-forms/uploads/php/files/rbc7v7kilatdo3p3edis6hsha0/goxur.pdf
    • http://umffz21.ru/admin/ckfinder/userfiles/files/21166029045.pdf
    • http://vankouwenenmastop.nl/UserFiles/file/92576624154.pdf
    • http://pietroquatriniarchitetto.eu/userfiles/files/dupunus.pdf
    • https://www.conkite.com/wp-content/plugins/super-forms/uploads/php/files/ca44f4cae6458211df234fe646130ac4/86225685354.pdf
    • http://bannermaul.com/userData/board/file/juzesefizonomareri.pdf
    • http://thecreditcrisis.net/clients/73966/File/13955225318.pdf
    • https://kede.org/userfiles/file/8344723882.pdf
    • http://wypelnienia.kratex.pl/wp-content/plugins/super-forms/uploads/php/files/3c70c1b27e7fa4e830d1d2046928c8b2/musonumovanerezotenovo.pdf
    • http://asirakademi.com/resimler/files/76133707211.pdf
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160afb5326db2a---87710104579.pdf
    • https://insights3.com/wp-content/plugins/super-forms/uploads/php/files/ea1a02fae34ae07f0ae2422c8ef9b87d/bimutufajobudusutiso.pdf
    • http://www.cargeacrew.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609c8894f358b---49401403737.pdf
    • http://imreelectric.sk/uploads/file/ganarojuredo.pdf
    • http://foire-fromages-et-vins.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b205a121fed---45927340952.pdf
    • https://cupanghitam.com/contents//files/pisunuwumujoluwab.pdf
    • http://brandnewgoods.net/userfiles/file/nebovosav.pdf
    • http://kennedy-jackson.com/clients/f/f7/f78508644b517540cdb1549d93860f53/File/65501559064.pdf
    • http://ecbpolska.pl/wp-content/plugins/super-forms/uploads/php/files/2950edafd434287d0dd2267448ce54fb/76302534464.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=paper+minecraft+online+free+games
    • 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_off0000fc9b.bin
b075902efcabbbc0f22da910c6cd7007013e5e4a8821e0a0d97ef60fdde21622
pdf-font-stream PDF embedded font (sfnt) at offset 0xFC9B 16848 bytes
font_01_sfnt_off000128bd.bin
92c1432bb85f4709e64bc18dcccd48053550f6a29af9abe425a4a9c2aa95a765
pdf-font-stream PDF embedded font (sfnt) at offset 0x128BD 10824 bytes
font_02_sfnt_off000141b8.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x141B8 16792 bytes