Malicious PDF — malware analysis report

Static analysis result for SHA-256 33c85d124f769716…

MALICIOUS

PDF

92.9 KB Created: 2021-09-03 03:01:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 5fcc6974be5adb17314e04b2addd2898 SHA-1: 2f4f1f71b804cfc0d2aba93aefd53f8ae5a66776 SHA-256: 33c85d124f7697162da05a340e0f2b176451662969444e4164a762818eb2da75
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs, several of which point to compromised WordPress upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of multiple links on disposable hosting and compromised CMS platforms suggests an attempt to obscure the ultimate destination or leverage existing vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9820

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://najlepsze-w-polsce.pl/uploads/8213292127.pdf In PDF document text
    • http://leprofit.ee/cmsfile/contentfiles/pefigoxupogiv.pdfIn PDF document text
    • https://www.ferienhof-schneider.de/wp-content/plugins/formcraft/file-upload/server/content/files/16073774f04ad2---zosasivudupeburavalep.pdfIn PDF document text
    • http://erh-hu.com/userfiles/file/bepilojoturogisidasim.pdfIn PDF document text
    • https://www.arc-welding.co.uk/wp-content/plugins/super-forms/uploads/php/files/8nuhs5bqsg5uiun0vfr1od8cle/10805303965.pdfIn PDF document text
    • http://shssailors1969.com/clients/3/36/366f78b21138e0f8005dfe6cc5e09e30/File/fazetek.pdfIn PDF document text
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/bn6eo97venjr5hq5bvql0dlg4f/vokora.pdfIn PDF document text
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608582479e000---8653616126.pdfIn PDF document text
    • https://www.alongsideasia.com/wp-content/plugins/super-forms/uploads/php/files/b03b1eefa327bc82a0bd0c2379fc49e5/gamuxiwebijobol.pdfIn PDF document text
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c7524a8e7ba---kanomuxanoxakesetit.pdfIn PDF document text
    • http://55thocscompany.com/clients/62662/File/94178480272.pdfIn PDF document text
    • http://www.udelimpa.es/ckfinder/userfiles/files/gujiziromodidozetabufe.pdfIn PDF document text
    • http://cadeco.com/testingsites/advantage_aviation/assets/media/file/kuketoxurusapaxoxabod.pdfIn PDF document text
    • http://seasonsblinds.com/uploads/ckfinder/userfiles/files/nalosufenud.pdfIn PDF document text
    • https://thinkglobalcompliance.com/ckfinder/userfiles/files/bitanibupezu.pdfIn PDF document text
    • http://termocity.by/pics/files/9016712765.pdfIn PDF document text
    • http://weighlessthisyear.com/ckfinder/userfiles/files/ladozu.pdfIn PDF document text
    • https://wedding-photos.cz/userfiles/file/zilaluwabegotepolinamazi.pdfIn PDF document text
    • https://memoservicesrl.it/file/85189055375.pdfIn PDF document text
    • https://marblobath.com/app/webroot/img/files/28285544539.pdfIn PDF document text
    • https://mekongtransport.com/upload/userfiles/files/40645976574.pdfIn PDF document text
    • http://vasset.bg/userfiles/file/nisomuzamepuvoxozaliloj.pdfIn PDF document text
    • https://astoriareiki.com/wp-content/plugins/super-forms/uploads/php/files/0aa71a23a0b52ccbe935c9d7c5a7e076/49628438516.pdfIn PDF document text
    • http://techbis.pl/files/file/zapolew.pdfIn PDF document text
    • https://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/4309afbe3391f84b3941868192ad9fda/gupewikejanobir.pdfIn PDF document text
    • https://kaptenhoki.info/contents//files/tusuwuzekubodagurasozim.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=ravens+schedule+2019+pdfPDF 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_off00010529.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10529 10980 bytes
SHA-256: a424320b433014677c9db3659e3718d4077f3a6b93a9714ccd3fc5433f6bf6a7
font_01_sfnt_off00011eb5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EB5 18296 bytes
SHA-256: 7971b7a7573de451bd37049f2155f6aeae14e77894e88b8f9db62ba9678c953d
font_02_sfnt_off00014e2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14E2A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1