Malicious PDF — malware analysis report

Static analysis result for SHA-256 44f28cb4173ea759…

MALICIOUS

PDF

74.3 KB Created: 2021-07-22 17:58:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 4edf7de6169c0e8be7644fa90433d650 SHA-1: 77346e76f755b6bd9251bbdb49f2dd17d61f498a SHA-256: 44f28cb4173ea75984974bd26778dbdc83a17b121d34a3f75483a50d8a266c99
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple compromised or disposable hosting sites. The embedded URLs and the overall structure suggest an attempt to exploit user trust by presenting a deceptive document that leads to further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

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 http://woods-china.cn/ci2/userfiles/files/20210629061037.pdf In PDF document text
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607ba3de8faf1---90834768894.pdfIn PDF document text
    • http://dichvuwebsites.com/media/ftp/file/lobepezu.pdfIn PDF document text
    • https://milliondollardesiclub.com/upload_files/featured/files/junevufimo.pdfIn PDF document text
    • http://kotolantopeni.cz/file/72532493444.pdfIn PDF document text
    • http://www.marcado.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160c857ce9eb96---46527672779.pdfIn PDF document text
    • https://zaragozadenoche.es/upload/files/64094354652.pdfIn PDF document text
    • https://amrapalispot.com/userfiles/file/39744641040.pdfIn PDF document text
    • http://adamlegal.com/userfiles/file/40973029382.pdfIn PDF document text
    • https://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607724a534dc2---78488039743.pdfIn PDF document text
    • http://altaprecision.com/userfiles/file/zunalogotagifazu.pdfIn PDF document text
    • http://botosani.ro/img/uploads/file/sozezolikotora.pdfIn PDF document text
    • https://www.ogblfrontaliers.fr/wp-content/plugins/super-forms/uploads/php/files/4ac9ltjhil5647g4dqo3vhj0u6/14256550696.pdfIn PDF document text
    • http://automsystem.com/UploadFile/file/20210508180940847.pdfIn PDF document text
    • https://www.abrasco.org.br/ckfinder/userfiles/files/fijewunetexe.pdfIn PDF document text
    • http://rapet.hu/files/rukat.pdfIn PDF document text
    • https://adikkeempat.com/contents//files/sawufukome.pdfIn PDF document text
    • http://romento.com/uploaded_files/userfiles/files/27526634547.pdfIn PDF document text
    • https://tuvanthietke13-5.com/webroot/img/files/gesofudokavipaxekosog.pdfIn PDF document text
    • http://coimbra.hu/uploads/ckfinder/userfiles/files/81047334641.pdfIn PDF document text
    • http://c2mag.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607089255be71---poxulixolowojawujo.pdfIn PDF document text
    • http://akicgiyim.com/userfiles/file/74947556140.pdfIn PDF document text
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/im219e2ulbqbak0ad1cag0n9fl/77004196768.pdfIn PDF document text
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/160df933d79b38---givesomuzipeme.pdfIn PDF document text
    • https://www.mysmilestudios.com/wp-content/plugins/super-forms/uploads/php/files/f61bb58674b9495f130afb4a96b8e5df/gokuwazexibakogilam.pdfIn PDF document text
    • https://psychotherapie-dr-albrecht.de/wp-content/plugins/formcraft/file-upload/server/content/files/16081a9369c40f---82032372020.pdfIn PDF document text
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160bd1323cc532---rugilokute.pdfIn PDF document text
    • http://altinay-law.com/images/file/88768452990.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=elements+present+in+quicklimePDF 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_off0000c71c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC71C 14092 bytes
SHA-256: 139f133080824c8f705ab34967926e65ffb2533a92c28f9d035810b3a62e5d1a
font_01_sfnt_off0000ea15.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA15 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001022c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1022C 10576 bytes
SHA-256: f0d71bfa910dd067d1d3d9dc732ef5f5fa90e91cf96a4e93c8f685a054c3212f