Malicious PDF — malware analysis report

Static analysis result for SHA-256 1aa588cfb4a9ac78…

MALICIOUS

PDF

91.0 KB Created: 2021-07-02 00:24:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: dcbd9efa575fa9c220088ded0270a743 SHA-1: eb8b7a808b3c4b3a2197e53e05932454ced2c249 SHA-256: 1aa588cfb4a9ac78fe0cc6357c9bd8e55dfdc354a34377cd6fb9f70c6132a2c9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm pointing to compromised WordPress upload directories, suggesting it's used to host or distribute malicious content. The presence of multiple distinct hosts and a high number of PDF links indicates a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://drukarnia-warszawa.pl/pliki/file/38854415972.pdf
    • http://steclotildehorton.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607ce9a6f3cd8---76823303430.pdf
    • https://heritagelogs.com/wp-content/plugins/super-forms/uploads/php/files/0vlj56k6el7d624riku8l3ig0o/wurab.pdf
    • http://biosite.ru/images/news/file/50790598136.pdf
    • https://oneremote.ru/wp-content/plugins/super-forms/uploads/php/files/a2e22004e193e712eec7d741d481f40e/suzawofewimopiwowosirunik.pdf
    • https://www.c2commercial.com/wp-content/plugins/super-forms/uploads/php/files/754e38836558a4fab4f79ea78a65f74b/wusawudozijijowogojadexo.pdf
    • https://pergamine.com/ckfinder/userfiles/files/kiguk.pdf
    • https://polskieplytki.com/wp-content/plugins/super-forms/uploads/php/files/5fa586da3794dcca67348ccab2373b7d/majutemuturasafavatoli.pdf
    • https://www.synergyheart2heart.team/wp-content/plugins/super-forms/uploads/php/files/ei8n8f6ltjd1o9hkvhkoi0c33a/lomilusuteru.pdf
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/16096ae5e23916---96066807547.pdf
    • https://regenerativetherapyforpain.com/wp-content/plugins/super-forms/uploads/php/files/191073130be34e50ac8a23d63ad439fc/87371474928.pdf
    • http://autoset66.ru/admin/ckfinder/userfiles/files/41560049204.pdf
    • http://darec.sk/files/files/18582879914.pdf
    • http://feriaalainversa.com/uploaded/files/fojikelij.pdf
    • http://kfbi.ru/content/file/ximibetozuvaba.pdf
    • http://www.sarajevo-inn-grunewald.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bec17f4e3a7---ledugupos.pdf
    • https://www.d-table.com/wp-content/plugins/super-forms/uploads/php/files/42612b96e3b174e060089c4646a1431e/72520844917.pdf
    • https://noble-worldwide.com/wp-content/plugins/super-forms/uploads/php/files/19ec63b15676c2d9dc99209548b5ecfb/66246584144.pdf
    • https://fiambreszav.com/wp-content/plugins/super-forms/uploads/php/files/7aa1d487d0cbcb01539abfc31844b7db/54377433518.pdf
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160bf683ca6116---25357772975.pdf
    • http://ecbpolska.pl/wp-content/plugins/super-forms/uploads/php/files/7fe10958d7fbccf77890dd1000f39c13/26986724633.pdf
    • http://oneself.pro/wp-content/plugins/formcraft/file-upload/server/content/files/1606e7367db35a---85813449345.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=heart+glyph+indesign
    • 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_off000100b2.bin
96f439c11b535402b4286bf6bc0d5fb4b61171c837d2bc35521458f2457832dd
pdf-font-stream PDF embedded font (sfnt) at offset 0x100B2 10656 bytes
font_01_sfnt_off000118c6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x118C6 16792 bytes
font_02_sfnt_off000130d8.bin
b1cb97e3e2107d11e4bf8bcd91dc831cba212ee3773fda31d0ba2c2467fa94ec
pdf-font-stream PDF embedded font (sfnt) at offset 0x130D8 17628 bytes