Malicious PDF — malware analysis report

Static analysis result for SHA-256 fcb875781f70c16e…

MALICIOUS

PDF

103.6 KB Created: 2021-07-30 05:57:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c2b411234d05a2236fd199c318f99422 SHA-1: 52f19ae363212f1ae45330288f65fd140102682f SHA-256: fcb875781f70c16eb6cbce15fb3547a597c21c7597726f7aae65d385948801c7
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple compromised or disposable hosting sites. The embedded URLs and the nature of the heuristics strongly suggest an attempt to lure victims to external sites for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9983

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://karat-dobremiasto.pl/userfiles/file/98987522476.pdf
    • http://www.heksan.com.pl/file/xoretuz.pdf
    • https://www.andeanskyline.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d3ce077d75---50232343255.pdf
    • http://tygodnikzuzlowy.pl/ckfinder/userfiles/files/17678061028.pdf
    • http://albertopizzetti.it/userfiles/files/rimanadakati.pdf
    • http://hoshitorionline.com/uploads/files/44496580971.pdf
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/1hrd40oohagt8ed1itaifct24q/mabituligosebujexevado.pdf
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/1609ce2b71df41---jijumikul.pdf
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086f2f7d469d---51765177070.pdf
    • https://clove7.com/userfiles/file/50093858032.pdf
    • http://dtcguild.org/clients/80367/File/41551333368.pdf
    • http://autobedrijvenindex.nl/images/uploads/93023130149.pdf
    • https://www.groupenahno.com/wp-content/plugins/super-forms/uploads/php/files/igm63ic5qcbkse7e58abq6fld2/jazuk.pdf
    • http://grapes4u.ca/sites/all/sites/grapes4u.ca/files/ruguxenufi.pdf
    • http://www.hj-bouwt.be/wp-content/plugins/formcraft/file-upload/server/content/files/1607154e2ee771---gusiribuwukorerowa.pdf
    • https://apexforestservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075a77642e47---87537228294.pdf
    • https://ddriu.hu/wp-content/plugins/super-forms/uploads/php/files/45681751b53ea95ea2c072836dbabcc3/gotozusamukeviwidu.pdf
    • https://defrokatilai.lt/images/files/wiguje.pdf
    • https://ta-taiwan.com/app/webroot/userfiles/files/56197159264.pdf
    • https://www.wflorlando.com/wp-content/plugins/super-forms/uploads/php/files/c0fedbffd9e4ac965d6012a4aed954aa/92190738535.pdf
    • https://viratrip.com/basefile/travelasreviracom/files/54040717485.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=hidruro+de+cromo
    • http://lovewhereyoulv.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/046e842213bedadda60b1a3861f6c0bf/jakotu.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_off00012dee.bin
0fc7bb432508715d539c80584c9a126c4c8f3795f319f657fea9614e764d1ee2
pdf-font-stream PDF embedded font (sfnt) at offset 0x12DEE 10044 bytes
font_01_sfnt_off00014430.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x14430 16792 bytes
font_02_sfnt_off00015c42.bin
a7b18307dcf74783574a8a8a04a1138ea229f1fa631c48509a05575b38fd6f51
pdf-font-stream PDF embedded font (sfnt) at offset 0x15C42 19780 bytes