Malicious PDF — malware analysis report

Static analysis result for SHA-256 0162713c165d7130…

MALICIOUS

PDF

76.5 KB Created: 2021-09-08 19:26:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 418e31c6c632a3825047fde3e065f1ad SHA-1: 6de677b2058bb0449e9542555ea1076a0494b2ce SHA-256: 0162713c165d7130a44ea9c77e58d327f9d5ecd996d4418adb3c9f29d3129308
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to other PDF files hosted on various domains. Several heuristics indicate this is a link farm, with some links pointing to compromised WordPress upload directories. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or distributing further malware. No scripts were extracted, but the structure itself is designed to lure users to external, potentially malicious, content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://jfhconsultancy.nl/userfiles/files/serurowopexasepazegodi.pdf In PDF document text
    • http://www.northern-japan.com/image/upload/File/22212746480.pdfIn PDF document text
    • http://matrixuniverzum.eu/wp-content/plugins/formcraft/file-upload/server/content/files/161346020d0c80---jipuxadeke.pdfIn PDF document text
    • https://www.swx.global/wp-content/plugins/super-forms/uploads/php/files/abb3c8deb610cc63558ec2ad27798fe3/6488267679.pdfIn PDF document text
    • http://allycatering.com/userfiles/55100388329.pdfIn PDF document text
    • http://industrialdevices.in/uploads/2971917387.pdfIn PDF document text
    • http://mygiftltd.com/userfiles/file/zegejowadijoxuwugir.pdfIn PDF document text
    • http://simoncaulkin.com/images/ganumulab.pdfIn PDF document text
    • http://ilkemymm.com/image/files/35512713002.pdfIn PDF document text
    • http://tischlerei-schlusche.de/sites/default/files/file/63644137280.pdfIn PDF document text
    • https://funcarele.com/ckfinder/userfiles/files/fosupezan.pdfIn PDF document text
    • http://abbeloosschinkels.be/userfiles/file/29531064764.pdfIn PDF document text
    • http://cuacuonnhaxuongbinhduong.com/upload/files/figosekolepuwa.pdfIn PDF document text
    • http://boletos.luzservicos.com/ckfinder/userfiles/files/zisefumunufusesowekewivog.pdfIn PDF document text
    • http://mg001.cn/upload_fck/file/2021-9-1/20210901160831880875.pdfIn PDF document text
    • http://geometracosentino.com/userfiles/files/60812828788.pdfIn PDF document text
    • https://pezenasenchantee.fr/userfiles/file/41105417415.pdfIn PDF document text
    • http://mrtowing.ca/Lawyers/userfiles/file/felolezofobadobemexib.pdfIn PDF document text
    • http://profisystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16138e1e56d903---sowixewasatufa.pdfIn PDF document text
    • http://goldnumber.info/userfiles/file/lujuz.pdfIn PDF document text
    • http://webs123.com/userfiles/file/zujufujoluxejeporifib.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=revit+architecture+2011+tutorial+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_off0000c6b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6B8 16880 bytes
SHA-256: 69e5f22c614b90b06f941e0296530110dc828392314eb2666471a36b014cf046
font_01_sfnt_off0000f258.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF258 10952 bytes
SHA-256: 631efbf146e2ac0b71de384cc40df01cd1cd1f07f60ae4be30182cecf5661834
font_02_sfnt_off00010bf0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BF0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1