Malicious PDF — malware analysis report

Static analysis result for SHA-256 52a4817d5df6877a…

MALICIOUS

PDF

83.5 KB Created: 2021-09-18 21:15:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 7169f5f74fcf927309a31f5600eff433 SHA-1: 331675aee5145535ff975ce05797b3b57381f4bc SHA-256: 52a4817d5df6877a9b669427356545c94c8224bdb3d73cebb7a0c2ea7d1d2b39
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, with numerous embedded URLs pointing to potentially compromised websites or disposable hosting, likely intended to lure users into downloading further malware or submitting credentials. The presence of external URI heuristics and link farm detection rules strongly supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 https://chcial.ru/uplcv?utm_term=shadow+fight+3+offline+hack PDF link annotation
    • https://best-of-geldanlagen.de/userfiles/file/39408257817.pdfIn PDF document text
    • http://botosani.ro/img/uploads/file/29034534383.pdfIn PDF document text
    • http://robedecreateur.com/img/files/13070551233.pdfIn PDF document text
    • https://atputasbazes.lv/images/userfiles/files/zijewegipovepav.pdfIn PDF document text
    • http://upakuika.com/img/file/mapisorawedidera.pdfIn PDF document text
    • https://latgalesamatnieki.lv/files/file/78890579631.pdfIn PDF document text
    • https://gfwofficial.com/ck_imgs/files/17107416979.pdfIn PDF document text
    • http://erago.cidees.com/uploads/files/94201838763.pdfIn PDF document text
    • http://devveb.net/userfiles/file/92842997493.pdfIn PDF document text
    • https://mudraconsultancy.com/uploads/files/58874074500.pdfIn PDF document text
    • http://cmrivestimenti.com/userfiles/files/78619378666.pdfIn PDF document text
    • http://www.jobsincrete.gr/images/_user_na/file/futod.pdfIn PDF document text
    • http://gorsilawfirm.com/userfiles/file/19981518917.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1612eac06bb169---moxawenuwe.pdfIn PDF document text
    • http://webbuilders.com/files/file/gakezuwurijofojika.pdfIn PDF document text
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cb2faee46a---6960016662.pdfIn PDF document text
    • http://chandravanshi.com/userfiles/file/20303414972.pdfIn PDF document text
    • https://zemiigori.com/uploads/file/1014707101.pdfIn PDF document text
    • http://myphamso1.net/uploads/files/tupepiv.pdfIn PDF document text
    • http://markfarolaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/69499571774.pdfIn PDF document text
    • https://kme.pl/global/app/webroot/uploads/file/16309924279515.pdfIn PDF document text
    • https://www.18fire.com/wp-content/plugins/super-forms/uploads/php/files/e888be8426bd0772fe1d79c6768309f9/jaxujej.pdfIn PDF document text
    • http://gldbirdgel.com/user_img/files/45247715080.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_off0000e23b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE23B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fa4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA4D 17384 bytes
SHA-256: 7061cce14606d524a325a37c0167882ab2efe3fa8fe71983728cfc3e8c7ee646
font_02_sfnt_off00012788.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12788 10912 bytes
SHA-256: bc01cea44633724e5d66fca19a7b7a5584e9a7f7ace846692dab6091e66fd8e1