Malicious PDF — malware analysis report

Static analysis result for SHA-256 1c320c85807d733d…

MALICIOUS

PDF

75.9 KB Created: 2021-09-14 09:30:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 97edafe31f1e8758dcc2536865b73fb3 SHA-1: f837d493115c59e6a0246a24eae3292ee9dc7e1b SHA-256: 1c320c85807d733d33eca5df280a296cf82c15602f3998256d0088246ce4d75b
156 Risk Score

Malware Insights

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

The PDF document contains a large number of external links, many of which point to compromised WordPress upload directories or disposable hosting, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://quangcaowebsite.vn/uploads/files/tunularitawefujosi.pdf In PDF document text
    • https://brincandoeaprendendo.com/fotosempresa/files/37305219938.pdfIn PDF document text
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16134d8cea6c05---zexataxupawamim.pdfIn PDF document text
    • https://ratoempat.com/contents/files/lomevezilakod.pdfIn PDF document text
    • http://www.mvdisposal.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138ef3025159---golujulukuw.pdfIn PDF document text
    • http://anaminfo.com/attachfile/file/22736536032.pdfIn PDF document text
    • https://2ruoteexpo.it/ckfinder/userfiles/files/97235249660.pdfIn PDF document text
    • https://cursosadistanciayonline.com/medios/files/30077792774.pdfIn PDF document text
    • http://gurolmumcu.com/userfiles/file/86024089837.pdfIn PDF document text
    • https://impariant-club.ru/wp-content/plugins/super-forms/uploads/php/files/6ae2a65518bb7edd6843818b105e71f5/kolapolipakodezozo.pdfIn PDF document text
    • https://bhiringisamsankalimandir.org/userfiles/file/dopesobogobejanokof.pdfIn PDF document text
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/cfe3b119758f179c6d6c6a413af6f7ba/kexegixebile.pdfIn PDF document text
    • https://kokomanis.com/contents/files/punuxovejurimixibuboxuke.pdfIn PDF document text
    • http://go-pxl.com/uploads/files/zofinagisutekesus.pdfIn PDF document text
    • http://lasfyy.com/uploadfile/file/20210910015403074.pdfIn PDF document text
    • http://freeware-software-download.de/uploads/editor/file/59877272997.pdfIn PDF document text
    • https://hunglivet.com/uploads/files/202109080101534050.pdfIn PDF document text
    • http://montex.pro/uploads/userfiles/file/36247042629.pdfIn PDF document text
    • https://motodubai.com/uploaded_images/files/nawulexotojozej.pdfIn PDF document text
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/16135fd4db84a8---zoniligigakizusakelubux.pdfIn PDF document text
    • https://xn--23-6kci4asohe8k.xn--p1ai/userfiles/file/82342450503.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=5000+solved+problems+in+organic+chemistry+pdfPDF link annotation
    • https://bxthirteen.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/399d251bf59493ec05c5d741aff91ef2/mojep.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_off0000c234.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC234 17252 bytes
SHA-256: 39dcfa012b46aacc1d079aaba4e1202fedff06be628ad0de200ecdeef1e2ea3d
font_01_sfnt_off0000ee5c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE5C 11544 bytes
SHA-256: 4fdefec8507b9ad424314714a72ce0265c2869f218c52b832281afe4bd7b3e42
font_02_sfnt_off00010927.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10927 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1