Malicious PDF — malware analysis report

Static analysis result for SHA-256 913fce60ad985457…

MALICIOUS

PDF

86.1 KB Created: 2021-09-23 19:46:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: cc12b112254ea78c5d530d26549e2122 SHA-1: cb441a1ff64fdc0fe55382cee1820ddb311aaf05 SHA-256: 913fce60ad98545765e33fb73f748b15b42f26b9b3dc863d35141b7589be06bc
204 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous links pointing to external PDF files. Several heuristics indicate these links are part of a link farm, some hosted on compromised WordPress sites or disposable domains, suggesting a phishing or malware distribution campaign. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 8

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://aibasavar.edu.bd/app/webroot/ckfinder/userfiles/files/83578286092.pdf
    • https://fullgame.hu/uploads/files/46421044174.pdf
    • https://dcmheavyequipment.com/admin/images/file/zutedosalut.pdf
    • http://murito.fr/ckfinder/userfiles/files/99676296137.pdf
    • http://elitk.ru/_files/30282279573.pdf
    • https://imad0c0.com/js/ckfinder/userfiles/files/48755605122.pdf
    • http://lab4050.com/upload/editor/file/33228412255.pdf
    • http://sofia-es.tokyo/yamituki-n/uploads/files/xapovebuz.pdf
    • http://oa30us.com/userfiles/file/subunovi.pdf
    • http://evo-models.com/uploads/userfiles/files/10366719020.pdf
    • https://pluviaterra.mx/wp-content/plugins/super-forms/uploads/php/files/3f4a9552379f97c25d2648801b088f4c/bometofapaxaj.pdf
    • http://em-ail.ch/pictures/2/91788291600.pdf
    • http://pspectr.ru/userfiles/file/worojifukeluduzelunulij.pdf
    • https://lakeshoresmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/osqtq77oo9du9e2k4fdd6quhq5/95042704931.pdf
    • http://noclegsosnowiec.pl/eurostyl/photos/file/4908554295.pdf
    • https://internationallanguagenavigators.com/media/minegupevimusoz.pdf
    • http://madinaboys.com/easydo%20v2.00/files/uploads/nanuvevudozilis.pdf
    • http://permagnet.com/upload_files/file/21091306290516663739mimc.pdf
    • http://www.gieskestukadoors.nl/ckfinder/files/files/buwetosevukajupin.pdf
    • http://terralis.net/catalogue_dynamique/file/dugedogof.pdf
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/161402be5182c0---39023197129.pdf
    • https://whereestar.com/marinarubicon/admin/file/23149479634.pdf
    • https://damsindia.org/admin/uploads/file/duvimodotagokokosoxo.pdf
    • http://njchemland.com/upload/files/23240846457.pdf
    • http://danchrisjewelry.com/userfiles/file/76934073657.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=apk+to+windows+app+converter
    • 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_off0000ec06.bin
ec75e2ada41ba8ab711d1381abb086b9b89436f8b54688a5ba4a4d99c9b67a62
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC06 17764 bytes
font_01_sfnt_off000119b1.bin
141f85e07d1887f24b696ba72590b38c9387de8f706c64414322bd5514962c33
pdf-font-stream PDF embedded font (sfnt) at offset 0x119B1 10684 bytes
font_02_sfnt_off0001327b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1327B 16792 bytes