Malicious PDF — malware analysis report

Static analysis result for SHA-256 e44b6eb432508a89…

MALICIOUS

PDF

87.3 KB Created: 2021-09-18 03:46:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 11c67a3bf85921d05a661bd6171b8126 SHA-1: c44fff28e394ab7d6856d1e3ab6808aeb88eb625 SHA-256: e44b6eb432508a897f4153f41a2b713e349d17d46c668d249416f853ee44346d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised websites or are part of link farms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or to serve further malicious content. The document body is heavily obfuscated and unreadable, providing no direct user-facing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://crewmak.ru/uplcv?utm_term=best+song+mixing+app+for+android PDF link annotation
    • https://invision.buzyhub.com/files/9578903967.pdfIn PDF document text
    • http://isotope3.pm-ural.com/uploads/files/54758302204.pdfIn PDF document text
    • http://www.cda.org.hk/ckfinder/userfiles/files/vibero.pdfIn PDF document text
    • https://groupunsur1.com/contents/files/rijiwonemetilinen.pdfIn PDF document text
    • http://kukubara.com/zdjecia/file/nufaveno.pdfIn PDF document text
    • http://thietkewebsite.btccorp.vn/uploads/files/bobepomapup.pdfIn PDF document text
    • http://karinameal.ru/imgdish/files/sazopememitiwukiw.pdfIn PDF document text
    • http://debnine.net/UserFiles/File/wijilajenetuw.pdfIn PDF document text
    • https://learnrkb.jugalbandiresearch.com/ckfinder/userfiles/files/fubosuletubugudase.pdfIn PDF document text
    • http://el-system.jp/uploads/2012/files/28864861268.pdfIn PDF document text
    • https://selispin.com/calisma2/files/uploads/xatosometikugodobik.pdfIn PDF document text
    • https://bnovum.hu/downloads/rokorofejomokizesi.pdfIn PDF document text
    • https://whitelightdesign.com/wp-content/plugins/super-forms/uploads/php/files/02bc8082c59277f8be4830b0730f4351/50097707738.pdfIn PDF document text
    • https://goldenparadisestsimons.com/wp-content/plugins/super-forms/uploads/php/files/670ff181c2ed14f1c6bb629002b8b384/kopefokitipede.pdfIn PDF document text
    • https://k9-warrior.com/wp-content/plugins/super-forms/uploads/php/files/o452ohadd1eriitcjr384ei9sd/348812970.pdfIn PDF document text
    • https://saleskerala.com/ckfinder/userfiles/files/57703025901.pdfIn PDF document text
    • http://moyamoya.center/images/hand_uploaded/files/12539854063.pdfIn PDF document text
    • http://turskazka.ru/ckfinder/userfiles/files/46844993321.pdfIn PDF document text
    • https://nangluongvada.com/uploads/files/gobiv.pdfIn PDF document text
    • http://goldcoil.com/uploadfiles/files/merewikexusujidixin.pdfIn PDF document text
    • http://vecsecity.info/editor_up/divarexukazoworusem.pdfIn PDF document text
    • http://swvocal.com/data/se2/file/nujojetomel.pdfIn PDF document text
    • http://www.training4thefuture.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613ba2e036f88---wifiwabi.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/161421b337c111---furumovas.pdfIn PDF document text
    • http://www.loockuniformes.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/161414099a7e70---zekasorezumi.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_off0000f0d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0D8 17624 bytes
SHA-256: 4ad4fd689107d8df516c9d1df05164c28775e22a5e2dc8a786f1e58ff427069f
font_01_sfnt_off00011e36.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E36 10948 bytes
SHA-256: 3f7f9322a6e44c9d7284bfa4e09ed1b9d51aabfbc11caa713ceec7181a03cc88
font_02_sfnt_off00013775.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13775 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1