Malicious PDF — malware analysis report

Static analysis result for SHA-256 c1bda19a7f5d3903…

MALICIOUS

PDF

86.5 KB Created: 2021-06-27 09:07:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9c8caa3f126811b2d42ca508c32d54c5 SHA-1: c07ea5ef900b8e39e3b77a1b98a80f05c79aa9e3 SHA-256: c1bda19a7f5d3903d78047730ac32f3a8ae7068712080c639c549070b33e8d4d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links, many pointing to compromised CMS upload directories and disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The primary attack vector appears to be users being tricked into opening this PDF, which then leads them to external, potentially harmful, content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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 https://holocaustresearch.pl/nowy/photo/file/lujolipugujomejagagome.pdf
    • https://prosegik.com/wp-content/plugins/super-forms/uploads/php/files/13a7319b7fc23e19346f6b6e3fc10ba0/74113102294.pdf
    • https://nuregio.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606d4de2653d8---woxisokowebes.pdf
    • http://sl-light.ru/design/img/upload/file/butozado.pdf
    • https://www.dolphinrfid.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088c87ce6e57---12933125606.pdf
    • https://www.synergyheart2heart.team/wp-content/plugins/super-forms/uploads/php/files/4193ib94kjqs6k4epp8ptmqaoh/26844814864.pdf
    • http://onestudent.dk/userfiles/file/36347504697.pdf
    • http://nitexprofi.cz/userfiles/file/9544547531.pdf
    • https://www.hungryalex.com/wp-content/plugins/super-forms/uploads/php/files/1f561987c6b08463a6a5f8e6087cc3f0/22345514009.pdf
    • http://ceskylakros.cz/userfiles/file/xijabukitepezozodubujuwo.pdf
    • https://energooptima.hu/upload/File/bidileraperapogoxitiroje.pdf
    • https://cornerstonelaw.eu/userfiles//file/94613809754.pdf
    • https://www.northernillumination.com/wp-content/plugins/super-forms/uploads/php/files/e55e15e9561015ceda76731c285f0800/52371597100.pdf
    • https://rsun.pro/admin/ckfinder/userfiles/files/87461765330.pdf
    • http://www.hotel-margherita.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070336470cce---konibuwosovofexewajis.pdf
    • https://actor-conseil.com/files/file/bukitug.pdf
    • http://kimhoatra.com/upload/fckimagesfile/36718608552.pdf
    • https://mytutr.com/wp-content/plugins/super-forms/uploads/php/files/b6c744d1798a775d8c24b47255bfa545/nivazikun.pdf
    • http://poorclarescork.ie/images/toninozusalatuperibiwujux.pdf
    • https://cbolean.com/wp-content/plugins/super-forms/uploads/php/files/gustcep7pbiasj7b6f4aqe0550/14063058670.pdf
    • http://www.britocunhaadvocacia.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/160812741af7b9---89421810469.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=moviesda+hollywood+movies+in+tamil
    • http://lovewhereyoulv.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/7f4abab42a6b732df596833a12824ea1/7120897898.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_off0000ee03.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEE03 16792 bytes
font_01_sfnt_off0001061a.bin
ba2c5ca7eae196bc7c68ada5f8922dc18ede3d9f26dd05b298648e3bf274d9e5
pdf-font-stream PDF embedded font (sfnt) at offset 0x1061A 10672 bytes
font_02_sfnt_off00011e78.bin
a2a1272dc235ff5142d14dfcde09affe3d6bf1090b85fc7a3ad9d69787383fe6
pdf-font-stream PDF embedded font (sfnt) at offset 0x11E78 17828 bytes