Malicious PDF — malware analysis report

Static analysis result for SHA-256 336f8a4a9fb55755…

MALICIOUS

PDF

111.7 KB Created: 2021-07-07 02:49:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1b27051d69a2c1647645f33a5230906d SHA-1: 3f2a7516cdf840ddf083be60be7551eddb88d227 SHA-256: 336f8a4a9fb55755a70387978d2ca0df9cff8177393dbdb02fb98bbe0fb01f5b
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many pointing to compromised WordPress sites, indicating it functions as a link farm. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the structure and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://spectrumohio.com/wp-content/plugins/super-forms/uploads/php/files/a18ee83a44c18d652d2c70592ec962cc/48688998281.pdf
    • https://fatheragneliti.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d7d100112cb---35185925079.pdf
    • http://impressivetravelvietnam.com/upload/files/lazesafejajufat.pdf
    • https://infravoip.com/wp-content/plugins/super-forms/uploads/php/files/1b2126d2cab3e046c0e46bf3db51bfb6/bulubo.pdf
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/0be3f9f4d4ced0a04a73cd10598dd101/80318453992.pdf
    • https://audreyheselmans.com/_files/file/14394347069.pdf
    • http://sibleyestateplanning.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/minujusumebewomelezewag.pdf
    • http://dioceseofniranam.org/userfiles/file/8769837843.pdf
    • http://www.kocay.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1607aebf605635---zawosegolulubedopulijaw.pdf
    • http://kookwarenhuis.nl/app/webroot/files/userfiles/files/woregulepaluderakajupo.pdf
    • http://kyanite.tv/userfiles/file/26188553868.pdf
    • http://sklepjola.pl/userfiles/file/56701225153.pdf
    • https://daiichitravel.com/uploads/news_file/suwaridovazaforananiwoti.pdf
    • https://engineeredrepinc.com/wp-content/plugins/super-forms/uploads/php/files/af0f6f38d741239c7265608c4acd4625/fizavenidebetetefa.pdf
    • http://dxczx.com/ckfinder/userfiles/files/20210603_061127.pdf
    • http://wakingbeauty.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b6567c0541e---supakakabimelitujune.pdf
    • http://cetinelektrik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1607134721ae6c---14364049536.pdf
    • https://ccveg.org/wp-content/plugins/super-forms/uploads/php/files/a2gnateiggco414bcnjfdais7u/86137724476.pdf
    • http://akinmedical.com/uploads/file/zumuguzujozunuzuxewus.pdf
    • http://asbufestival.com/uploads/FCK_files/file/mawomum.pdf
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609830820c937---numijazikanarujofo.pdf
    • http://jhroseclassof77.com/clients/45984/File/17109446386.pdf
    • https://simovi.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160dc11269fc48---97757230443.pdf
    • http://zdravi-kromeriz.cz/files/file/73831899555.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=adjectives+starting+in+b
    • 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_off000157d6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x157D6 16792 bytes
font_01_sfnt_off00016fe8.bin
f37e364e22af0aeed84a22536a6daca67002327b046c0c8c66a9e354a13838b3
pdf-font-stream PDF embedded font (sfnt) at offset 0x16FE8 16084 bytes
font_02_sfnt_off00019961.bin
198d0946050ddd7f4b28d0b80abdd834c277a71efc36d06a6658fb93fc0fbd61
pdf-font-stream PDF embedded font (sfnt) at offset 0x19961 10696 bytes