Malicious PDF — malware analysis report

Static analysis result for SHA-256 f483736dfe39b322…

MALICIOUS

PDF

76.9 KB Created: 2021-09-10 16:44:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 394ed4798cf1e307b26bdf989fe647eb SHA-1: 0931939d6ad4bb9475a20ce50acdba491099fe69 SHA-256: f483736dfe39b32290b5f93fa4284badba67d4f09b91f724110ee56bb8766f07
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF containing numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicative of a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, but the PDF structure itself is used to host a collection of links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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 http://samtekelektrik.com/files/12351434936.pdf
    • http://biplano.eu/userfiles/files/dojigirinaf.pdf
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16134e7879e3a2---vesenoralowapot.pdf
    • https://wlao.on.ca/wp-content/plugins/super-forms/uploads/php/files/d8c72cf8151dac9d8dd0eb9f28f56788/xanepojiwajuzalizida.pdf
    • http://geodeslaboratori.eu/userfiles/files/xovutofojitujilude.pdf
    • http://reafamily.lt/ckfinder/userfiles/files/kiwogixeguwotefoka.pdf
    • https://www.denisonlandscaping.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138ce6e532bb---mewimefazu.pdf
    • https://carthink.org/wp-content/plugins/formcraft/file-upload/server/content/files/1612eb345504f5---rojenufopemivavobupegeni.pdf
    • https://www.pactforfamilies.org/ckfinder/userfiles/files/wusujizemepugazakitu.pdf
    • http://asustainable.com/global/file/81972466746.pdf
    • https://korvioinfotech.com/ckfinder/userfiles/files/jigozajidoripokeraleke.pdf
    • http://pvvc.cz/files/12118057275.pdf
    • https://michaels-limo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613053a5e8764---69559847710.pdf
    • http://erkerlaender.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613626f5ee662---zoxufa.pdf
    • http://smalternatywa.pl/media/upload/files/889d685fa22087944417ef97dae3b334.pdf
    • http://wizclub.net/upload/userfiles/file/dilapubufinimugukevej.pdf
    • http://portaldo.eu/contenuti/upload/file/dodekatepuxikenatomaxa.pdf
    • https://iqrainternationalschool.org/_assets/files/5000233877.pdf
    • https://keluargamimpi.com/contents/files/26475597424.pdf
    • https://ehlibeytalimleri.com/resimler/files/90947724066.pdf
    • https://minipowerpack.net/upload/files/robipuwotozudosege.pdf
    • https://relans-nn.ru/images/docs/file/32760994515.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=stock+tracker+android
    • 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_off0000c8f3.bin
16b8feaa763a6c15695d560866018a9c42a27e5fb6b47f6ae18ea2f9253ac20a
pdf-font-stream PDF embedded font (sfnt) at offset 0xC8F3 17488 bytes
font_01_sfnt_off0000f6b1.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF6B1 16792 bytes
font_02_sfnt_off00010ec8.bin
830710c197b974e6bc494beb489223a02297f7d81e050645895c473d1312b1d3
pdf-font-stream PDF embedded font (sfnt) at offset 0x10EC8 10316 bytes