Malicious PDF — malware analysis report

Static analysis result for SHA-256 f66cf4edba72be58…

MALICIOUS

PDF

75.8 KB Created: 2021-09-08 03:32:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 43c4e5e7e7a0f69e1ac98af780e1d837 SHA-1: 2fa517a9e0b02a5c22a10a04d629e77b0f9db3fe SHA-256: f66cf4edba72be5885e3d2d9fed778a09830891680a03863ae50b48b0770a94c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged by multiple heuristics and a machine learning classifier as malicious, specifically as a phishing or trojan delivery mechanism. It contains numerous links to external websites, many hosted on compromised or disposable domains, suggesting a link farm designed to redirect users to malicious content. The presence of embedded URLs and the nature of the heuristics indicate an attempt to exploit users through deceptive links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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://smidgel.ru/uplcv?utm_term=sciatica+exercises+for+elderly+pdf
    • http://jubileejec.com/userfiles/files/73631573198.pdf
    • https://aksusu.com/upload/files/dokozowudit.pdf
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160ab4bafdb5e5---xofopiwodixeninix.pdf
    • https://www.modianodesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607dfd22617eb---noviwavofizolawoxafelug.pdf
    • https://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b4d4b809077---gavoxe.pdf
    • http://poetische-malerei.de/web/editor/files/25437088808.pdf
    • https://www.coconutlodge.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074a9499d7be---megonoravu.pdf
    • https://all-stage-meditation.tw/uploads/files/61250600b9126.pdf
    • https://zapret-rf.org/web/img/podborky/files/92719916876.pdf
    • http://guides2alpes.fr/uploads/file/virami.pdf
    • https://www.infratechgroep.nl/wp-content/plugins/super-forms/uploads/php/files/2ed7e844f61c47f7e0fd8b1647842e16/31314926715.pdf
    • https://adetexfoamgroup.centralcms.cloud/galeria/files/pitibowuduzekapu.pdf
    • http://www.heatandgas.com//EditorImages/file/11971794981.pdf
    • https://wolfgang-photography.com/userfiles/files/xuwevebaxaninezuxorupazaj.pdf
    • http://sk-uralstroy.ru/uploads/files/1667579207.pdf
    • https://sitebyside.ru/wp-content/plugins/super-forms/uploads/php/files/c4169a1e59387c5ec0806eaf5ae12309/64031464538.pdf
    • http://ziepniekkalns.lv/wp-content/plugins/formcraft/file-upload/server/content/files/1607591ba12243---busenubomosiwobimofadidi.pdf
    • http://nyett.hk/uploads/news/files/domotazabenug.pdf
    • http://dxczx.com/ckfinder/userfiles/files/20210714_093347.pdf
    • https://www.makathastaliklari.net/wp-content/plugins/formcraft/file-upload/server/content/files/160777f3fc4ebd---18545927564.pdf
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160a55dde49bd8---81830335060.pdf
    • https://hoffmanowska.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16095d8ea01f40---6039717210.pdf
    • http://ahlhy.com/uploads/file/072201518875.pdf
    • http://english-island.pl/wp-content/plugins/super-forms/uploads/php/files/lb41dn40t0oerkv7akf40dp0r4/70332718239.pdf
    • https://amalighting.com/wp-content/plugins/super-forms/uploads/php/files/a23c14fbe8312ce7d2ee6162bd75fc7f/48806922338.pdf
    • http://shuswapladystriders.ca/userfiles/file/buwidibubapagevilabejoxo.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_off0000c650.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC650 16792 bytes
font_01_sfnt_off0000de62.bin
0b0a9a26652009bcb224ab1cd690b17ffc712d38ba9552692a8efde805619cef
pdf-font-stream PDF embedded font (sfnt) at offset 0xDE62 16900 bytes
font_02_sfnt_off000108a8.bin
c5aa69f6239e01298cfac748a03c102723bc4086f5ec70000ff9619f4821f41b
pdf-font-stream PDF embedded font (sfnt) at offset 0x108A8 10800 bytes