Malicious PDF — malware analysis report

Static analysis result for SHA-256 23ad36a335fe2f59…

MALICIOUS

PDF

93.9 KB Created: 2021-07-01 10:16:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ef73d313d61533810f0eeb3722b6213d SHA-1: a4f8783ca18c3df5f870dcc99c5f499f5c3524de SHA-256: 23ad36a335fe2f59dd19555747b8d6ce8a76a015a18efd50e9547a118db670b2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains a link farm pointing to multiple compromised WordPress sites, suggesting an attempt to distribute malicious content or phish users. The presence of embedded URLs and the nature of the heuristics indicate a phishing or malware distribution campaign, likely initiated via spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://recamonde.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160983ff56818d---judovadusifatevuxizut.pdf
    • http://sinara.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a5007e43159---16439138099.pdf
    • https://soudurelauziere.com/upload/editor/file/mowuzoxewabajuk.pdf
    • https://flylights.pl/wp-content/plugins/super-forms/uploads/php/files/gcgisl7fmckhlqjafiqj68ijhi/21824438163.pdf
    • http://plafondchauffant.fr//img/user/file/69605952468.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160918207640e1---nodupuban.pdf
    • http://www.peopleoftheheath.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c35becc867c---xivupep.pdf
    • https://takeorders.online/wp-content/plugins/super-forms/uploads/php/files/p6sfamakag1njj3e51421ogg85/daxugimekijakojegikagun.pdf
    • https://lightingsystemscol.com/wp-content/plugins/super-forms/uploads/php/files/e0919310ba77c90cb82327d71fb1c86c/jijotiwulajinila.pdf
    • http://ahcxdq.com/uploads/file/281950171696.pdf
    • https://www.marvistasales.com/wp-content/plugins/super-forms/uploads/php/files/e6df8eb2a31f064aac0d12bbefddd362/toxutafumogivonup.pdf
    • https://assurancemauricie.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607616ee3fd50---35794475601.pdf
    • http://thm-holding.ru/wp-content/plugins/super-forms/uploads/php/files/74c0b50e5cc59760686129903ca82e7d/63228467999.pdf
    • http://omniatel.it/wp-content/plugins/formcraft/file-upload/server/content/files/1609c1f93106a0---32878728176.pdf
    • https://pointsourcegroup.com/wp-content/plugins/super-forms/uploads/php/files/a069995eec70c066984e03206c1700bb/96518903905.pdf
    • http://kulturazebrak.cz/userfiles/2970648566.pdf
    • https://xn----8sbaavnccwq4am.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/180e150edecc10fc892195b48ad9a3a2/72235741232.pdf
    • https://mziagroup.com/wp-content/plugins/super-forms/uploads/php/files/s82d7jaergv1tfdl6mpipqqipi/nodimejojifexije.pdf
    • https://terravistahometeam.com/wp-content/plugins/super-forms/uploads/php/files/c42b142810ba6611d620bca664c4b453/54668800571.pdf
    • http://creptiles.dk/userfiles/file/17660709550.pdf
    • http://zaragozalawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/52090614945.pdf
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ad83ffb96ee---tanafepilajojez.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=10th+ssc+science+important+questions+pdf+2020
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010317.bin
592bb9ad83023282e287f129a9d7d9ca970565c5beab8c6f3be4aed2c539d5c8
pdf-font-stream PDF embedded font (sfnt) at offset 0x10317 11280 bytes
font_01_sfnt_off00011d37.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11D37 16792 bytes
font_02_sfnt_off00013514.bin
aa05cf079b0d51a179545f5e62b3a4c6ff1088f47710f8d6c04d42c0465d7343
pdf-font-stream PDF embedded font (sfnt) at offset 0x13514 1224 bytes
font_03_sfnt_off00013c2d.bin
e0a691b849f7ea4ec74f1f68a0042e45a2af822f326fd7fa0e38db7770f8f078
pdf-font-stream PDF embedded font (sfnt) at offset 0x13C2D 17348 bytes