Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1f97641487d9f1a…

MALICIOUS

PDF

83.7 KB Created: 2021-09-02 00:14:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: fac4b24c934ab157d5fdf04a541219e2 SHA-1: 3184a7eb5b8f16868bb5bfe8c670c64ce85940ee SHA-256: a1f97641487d9f1af7572b46e1b385107f770b789689432285db8cb0fb4f0107
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous URLs, many hosted on compromised WordPress sites and disposable domains, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body is heavily obfuscated and unreadable, providing no direct user-facing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9925

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://pttaccounting.com/userfiles/files/37547200455.pdf In PDF document text
    • http://www.insurancedirectcanada.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160ae9a306bc45---53201384253.pdfIn PDF document text
    • https://www.ezhealthcheck.com/wp-content/plugins/super-forms/uploads/php/files/4msq19m449pnspghjckjbi5opt/radurewufavumolus.pdfIn PDF document text
    • https://pensiuneavlasin.ro/wp-content/plugins/super-forms/uploads/php/files/8ilkulr310eir0oajgkjh7la0r/xinizuludowil.pdfIn PDF document text
    • https://aljazeerahpetroleum.ae/userfiles/files/51345902802.pdfIn PDF document text
    • http://stylist.in.ua/wp-content/plugins/formcraft/file-upload/server/content/files/1606f189e30cfa---kuxijeku.pdfIn PDF document text
    • http://banquat.com/userfiles/files/lesorazivomofimek.pdfIn PDF document text
    • http://sartor.ru/upload/files/vanozuguvigujuvurus.pdfIn PDF document text
    • http://ibarugi.com/fckeditor/userfiles/file/fanid.pdfIn PDF document text
    • https://www.hdontheroadnapoli.it/wp-content/plugins/formcraft/file-upload/server/content/files/16089096d7ab98---46945847649.pdfIn PDF document text
    • http://erfolgsapp.de/wp-content/plugins/formcraft/file-upload/server/content/files/160aa5ba3e924e---jorivurusememegamapurisag.pdfIn PDF document text
    • http://www.julitolaschools.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071654e3e49f---49454239457.pdfIn PDF document text
    • http://mail-ex.net/userfiles/file/72720099388.pdfIn PDF document text
    • http://andreevmag.com/wp-content/plugins/super-forms/uploads/php/files/83987e67a7abfe987fe8975c77d95e80/jenovujerikepelotasa.pdfIn PDF document text
    • https://iphonerepairservice.nl/app/webroot/files/userfiles/files/pesewojurofek.pdfIn PDF document text
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb2b087ccec---40762107088.pdfIn PDF document text
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/592ba009f88fcb2cd290f917b951e00e/julawog.pdfIn PDF document text
    • http://www.lifestaralberta.com/wp-content/plugins/formcraft/file-upload/server/content/files/16095aa5998e2c---taruxur.pdfIn PDF document text
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606cce84d889a---97618295343.pdfIn PDF document text
    • http://charivne.info/images/file/kemavabilupexase.pdfIn PDF document text
    • http://kartelabasligi.com/images_upload/files/sawiveliborevuzafab.pdfIn PDF document text
    • http://xn--eyt274i.com/upload/files/kiwavata.pdfIn PDF document text
    • https://fwullong.com/upfiles/editor/files/mibusesisaw.pdfIn PDF document text
    • http://bluecars.pl/userfiles/file/78726288803.pdfIn PDF document text
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/16121912880d9a---kagobivevubunepetu.pdfIn PDF document text
    • http://businesslegalgroup.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/3644971270.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=functional+urinary+incontinencePDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e674.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE674 16468 bytes
SHA-256: 7c8792944353fde109f777ac61e79c8b4d6969ddcb77418b2cf3da72df8e2f7e
font_01_sfnt_off000110f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110F8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001290f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1290F 10248 bytes
SHA-256: 1d33c2f3d1f0be1d4a9e3651e6f1731da67f947f8cc57a3d4ad5105f4ef28521