Malicious PDF — malware analysis report

Static analysis result for SHA-256 41448b968e9c92b4…

MALICIOUS

PDF

83.3 KB Created: 2021-07-08 07:44:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: ac69fa2f3a91c8535033f223c756a206 SHA-1: dc344ee520370b67f9384ed307b23f1af94cd7c6 SHA-256: 41448b968e9c92b4a348d9676d3f459ba12e244d6775f4d583371bb1ee5ab653
164 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or malware distribution attempt. It functions as a link farm, directing users to multiple external URLs, some of which are hosted on compromised WordPress sites. The presence of numerous links and the use of 'utm_term' parameters suggest an effort to lure users to potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 7

  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://coretry.ru/uplcv?utm_term=bsc+nursing+questions+and+answers PDF link annotation
    • https://www.karavanlakesfet.com/wp-content/plugins/super-forms/uploads/php/files/460a7d89cd812a2a291214cc8419458b/17088311239.pdfIn PDF document text
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/160788248aef3f---6539702690.pdfIn PDF document text
    • https://laser-arena.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160885152d4c68---55822499800.pdfIn PDF document text
    • http://orchid-daikanyama.com/userfiles/file/ratovuxisonu.pdfIn PDF document text
    • https://partner-support.net/user_data/userfiles/files/14824156111.pdfIn PDF document text
    • https://pensiuneavlasin.ro/wp-content/plugins/super-forms/uploads/php/files/1m249as7hcfi520p2cqg78t2pa/34781104121.pdfIn PDF document text
    • http://ifa-astrologie.de/userfiles/file/83380213401.pdfIn PDF document text
    • http://creativetechno.in/userfiles/file/19027199411.pdfIn PDF document text
    • https://sipare.com.ar/wp-content/plugins/super-forms/uploads/php/files/e4b0r13vu241n2ku2nsc5917qg/nufipakuzimaxedamop.pdfIn PDF document text
    • http://peggylittlelawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/40290167659.pdfIn PDF document text
    • http://iwilldoit.ru/uploads/files/files/lakufojodijajodot.pdfIn PDF document text
    • https://admonks.ru/wp-content/plugins/super-forms/uploads/php/files/4d93ed158687af05b4dde164db07d92b/zimasutorifuzipirowuno.pdfIn PDF document text
    • https://dejavuruse.com/userfiles/file/27485016947.pdfIn PDF document text
    • https://bisnismedsos.com/userfiles/file/60630157253.pdfIn PDF document text
    • http://dabaizhongxue.com/upload_fck/file/2021-7-3/20210703091812541941.pdfIn PDF document text
    • https://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a10abae78b3---6407744203.pdfIn PDF document text
    • http://avanti-kuhni.ru/upload/files/gokokefiwel.pdfIn PDF document text
    • 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_off0000e341.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE341 10884 bytes
SHA-256: 743af0db516b04523ecc14f80a578a4a27dc52c67649c1509c4b85b98488c092
font_01_sfnt_off0000fc1f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC1F 17020 bytes
SHA-256: 798e753adf98e17d707a500c89b2a76aeae1a1cded7607cdc279c7a81d15c326
font_02_sfnt_off0001285b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1285B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1