Malicious PDF — malware analysis report

Static analysis result for SHA-256 57c1223728a5ed2d…

MALICIOUS

PDF

96.1 KB Created: 2021-06-27 05:48:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 2e5fe64ddc1ef76f36f36c1ae4f8626f SHA-1: 013d1b682dec45148cedaa7587406d55bb231ca8 SHA-256: 57c1223728a5ed2da1f4730ea9f73968e0002aebcd241d4402c5fce2f8388033
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites. The ML classifier strongly indicated maliciousness, and the link farm structure suggests an attempt to direct users to potentially harmful content or phishing sites. No scripts were extracted, limiting the analysis of direct execution vectors.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9822

Heuristics 5

  • 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://kusadasidentalclinic.com/img/userfiles/files/8899170014.pdf In PDF document text
    • https://atlanthealth.com/wp-content/plugins/super-forms/uploads/php/files/5ec353c712073928c6d9f870dbe45994/3893328713.pdfIn PDF document text
    • http://ylgems.com/file_media/file_image/file/zajonowugugigobatufamija.pdfIn PDF document text
    • http://philippinesroadshow.com/wp-content/plugins/super-forms/uploads/php/files/846907a4ccaa9976c496044703482cd1/medazen.pdfIn PDF document text
    • https://www.ptlittleflower.org/wp-content/plugins/super-forms/uploads/php/files/fim0raphc5b2ae437bo6vueqo3/debukamogunetalobu.pdfIn PDF document text
    • http://aarogyamedico.com/userfiles/file/97413454303.pdfIn PDF document text
    • http://akcjonariusz.com/UserFiles/file/48595177633.pdfIn PDF document text
    • http://oticonshop.net/ckfinder/userfiles/files/92023084951.pdfIn PDF document text
    • https://ketgate.eu/wp-content/plugins/super-forms/uploads/php/files/7644dc51133b42a143a5cbeea6d2108f/49752973046.pdfIn PDF document text
    • https://greyquotient.com/wp-content/plugins/super-forms/uploads/php/files/9f4a0af4cae6ab39eda08d0e0200585d/vuwibuki.pdfIn PDF document text
    • https://relleno-acidohialuronico.com/wp-content/plugins/super-forms/uploads/php/files/8a7818f5d4966e389d0a815db4bfc154/donemukofiromejobiv.pdfIn PDF document text
    • https://adasms.fr/userfiles/file/18104996567.pdfIn PDF document text
    • http://usaoxin.com/userfiles/2021-6/file/13368589688.pdfIn PDF document text
    • http://www.jhannahs.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094068a29eb1---73204495554.pdfIn PDF document text
    • https://www.northamericatalk.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609085ae76961---jedakaziwetibuvaxeruwuvix.pdfIn PDF document text
    • http://www.adanakursmerkezi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086eb64e24d2---xesozisekunedojovefofuj.pdfIn PDF document text
    • http://dioceseofniranam.org/userfiles/file/wasirorejerakidogosa.pdfIn PDF document text
    • http://circuitvietnamcambodge.com/hinhanh/file/55814903303.pdfIn PDF document text
    • http://www.fotografoeventimilano.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084b70a84514---tefutogagigamujewa.pdfIn PDF document text
    • https://sirikulsteel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b45c43a7568---tosomanafeteb.pdfIn PDF document text
    • https://elearning-chemistry.ro/userfiles/file/rivoferamoxepawur.pdfIn PDF document text
    • https://almoheetmanpower.com/public_html/userfiles/file/pogaguposenetoripuzuxof.pdfIn PDF document text
    • https://www.mixedclass.com.au/wp-content/plugins/super-forms/uploads/php/files/21bg12aujhq0md653nvcrmpn1t/48240864897.pdfIn PDF document text
    • https://nothingbutsafetyglasses.com/userfiles/file/xesafuxejevi.pdfIn PDF document text
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607d56cb3681b---11212343829.pdfIn PDF document text
    • http://bouncebodysupplements.com/newerac2c/userfiles/file/71968625800.pdfIn PDF document text
    • http://pinturasoltra.com/images/slider/files/xusukikizefu.pdfIn PDF document text
    • http://banglatalkies.com/dynamic-images/cms/file/lewepukonovifufi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=commentary+scientific+paperPDF 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_off00011108.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11108 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001291f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1291F 10740 bytes
SHA-256: a56ff8fe67f00e6152bf1d5ee32d49a41c091703c8b6fd4189ee508a4394f51f
font_02_sfnt_off000141e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x141E4 18112 bytes
SHA-256: 8b486854217e915089276358b713ccdc4c1715792bf7b34856ce7c961c8c7a1a