Malicious PDF — malware analysis report

Static analysis result for SHA-256 28a88458585f31a0…

MALICIOUS

PDF

95.6 KB Created: 2021-07-05 12:51:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f96de9bf709372b56c6c57e9c0a6f438 SHA-1: b4a1b934bc5943729e0e62ec50f38a97b3e0dea5 SHA-256: 28a88458585f31a04a2da4939740ef109713d7da8fbcb9a9ba1c7aae06f60781
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to compromised WordPress sites and disposable hosting, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the structure and embedded URLs are indicative of a phishing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9935

Heuristics 6

  • 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.
  • 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://inwebjor.ru/uplcv?utm_term=high+fructose+glucose+syrup
    • http://sieckultury.pl/wp-content/plugins/super-forms/uploads/php/files/a2125167cb6f0ed28e21768fc017ff1a/25374862622.pdf
    • http://tencanpowder.com/d/files/14329764075.pdf
    • http://stevis.cz/files/file/59116099370.pdf
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/160c5d73109f01---lezupitexagufuze.pdf
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092fd57aa248---20883533431.pdf
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/160b4426d8a05b---19728457534.pdf
    • https://fastcomputer.vn/wp-content/plugins/super-forms/uploads/php/files/2891b15441489074d9b49207e4974280/84313783178.pdf
    • https://aashianarealty.com/file/mezidarogabezakira.pdf
    • https://client-sms.com/ckfinder/userfiles/files/nerebeju.pdf
    • http://israel-aliya.com/wp-content/plugins/super-forms/uploads/php/files/86ebdb4777c3202e292993b4980cd4f2/16620468475.pdf
    • https://www.paparazzirestaurant.com.au/wp-content/plugins/super-forms/uploads/php/files/0808803613da77a4fb6baeaa45fa3923/sufijoxizuragagaxineba.pdf
    • https://miamiuniquelimo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608298e861bd2---lanux.pdf
    • http://wagnerpc.com/userfiles/files/xikalimojuwudufiniva.pdf
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/f242207db44f2c799e69782615c9d958/temewosobafobabolefovowub.pdf
    • https://dentinale.eu/wp-content/plugins/super-forms/uploads/php/files/9073d99a7e088fb1e15e94e578feb87d/bixepizogujiga.pdf
    • http://gemwishrs.com/ckfinder/stones/files/repadosekovodirex.pdf
    • http://tomaszskiba.com/userfiles/file/73238858025.pdf
    • http://ruihuitax.com/files/file/repopuwivegulubemotapin.pdf
    • http://www.sarajevo-inn-grunewald.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ade89d2a13e---99230932904.pdf
    • https://www.gs-gleichmann.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c3ead24cf7e---pegesatutubiditolo.pdf
    • https://alate.org/admin/fckeditor/editorfile/93028752806.pdf
    • https://simovi.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160927c7bb029d---1722685670.pdf
    • http://bangkoksolarpower.com/syner_upload/images/files/narivolojixaji.pdf
    • http://orchid-daikanyama.com/userfiles/file/xaxofefinomusevule.pdf
    • 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_off00010fe9.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10FE9 16792 bytes
font_01_sfnt_off00012800.bin
f2fff09b2ee58583bdd12edf25def05e107ab438414c9aa1f771cf74ceb0375a
pdf-font-stream PDF embedded font (sfnt) at offset 0x12800 10696 bytes
font_02_sfnt_off000140b0.bin
e801e858e5f01faa965aa748b371d35ac78ce9dc90d95f480b87d2d35700f503
pdf-font-stream PDF embedded font (sfnt) at offset 0x140B0 18520 bytes