Malicious PDF — malware analysis report

Static analysis result for SHA-256 66117a44ced5dd5d…

MALICIOUS

PDF

87.2 KB Created: 2021-07-01 21:59:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 24893303ab11fb1b5f428bcb0ff1f47b SHA-1: 7636ec10a09e6be955a08cb3f3d7e05a9fdee9e5 SHA-256: 66117a44ced5dd5d3e3d72a4bac9d6b0c73b9371e7387995012e985ad539914b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

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 WordPress sites and disposable hosting domains. While no scripts were explicitly extracted, the PDF structure and the nature of the URLs suggest potential for JavaScript execution or exploitation to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://krisoc.ru/uplcv?utm_term=new+weapons+of+world+war+1+worksheet+answers PDF link annotation
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/fphek972gimt7h8c5h8drbugjv/zelirajugejajuluvejuti.pdfIn PDF document text
    • https://www.elektrobetrieb-scholz.de/wp-content/plugins/formcraft/file-upload/server/content/files/16076822ebaa85---wamabomubemafonibadenore.pdfIn PDF document text
    • http://ccswcd.com/userfiles/file/xupozinezired.pdfIn PDF document text
    • http://ebslang.net/_UploadFile/Images/file/63103621906.pdfIn PDF document text
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16079c02b3f730---xupixib.pdfIn PDF document text
    • https://globalclassic.org/wp-content/plugins/super-forms/uploads/php/files/cagb9mq3snau5267v7ftdqlui0/jorizanujip.pdfIn PDF document text
    • http://liveisagenix.com/ckfinder/userfiles/files/finuselifa.pdfIn PDF document text
    • http://creativeindustries.ru/uploads/userfiles/file/nutukesaw.pdfIn PDF document text
    • https://gpuhub.net/wp-content/plugins/super-forms/uploads/php/files/9bospskcdu7r22jei9tfqstjjs/domunixenomitofagepu.pdfIn PDF document text
    • https://miamivanservice.net/wp-content/plugins/formcraft/file-upload/server/content/files/1608108414b06c---76772290260.pdfIn PDF document text
    • http://klubalfa.org/img/userfiles/file/50838243788.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/f9j5s4571dscmgisfvjr5o43s6/lifaruvadijogakubutuva.pdfIn PDF document text
    • http://minicabii.com/survey/userfiles/files/77570898141.pdfIn PDF document text
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c6e509a42c4---78398506746.pdfIn PDF document text
    • https://motelandratecuci.ro/userfiles/file/189468497.pdfIn PDF document text
    • http://www.yoko-ono.be/images/userfiles/file/98597078975.pdfIn PDF document text
    • https://ferado.vn/userfiles/file/92607909267.pdfIn PDF document text
    • https://www.vedaaz.com/wp-content/plugins/super-forms/uploads/php/files/af4dc6970fd34765aa57d70b765943d4/kidolafifa.pdfIn PDF document text
    • http://inlikeflintlogistics.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075a8a933bce---sopinejidivu.pdfIn PDF document text
    • https://vashadvokat82.ru/wp-content/plugins/super-forms/uploads/php/files/d4e5c865e36695c9fcdee6e57c0820c7/80910500825.pdfIn PDF document text
    • http://mfplus.ba/wp-content/plugins/formcraft/file-upload/server/content/files/1608d23f384cc4---puwakozipel.pdfIn PDF document text
    • http://21cedu.com/pds/userfiles/files/dinoforuvibidizeke.pdfIn PDF document text
    • http://harrisonfamilyreunion.org/clients/868801/File/36507768124.pdfIn PDF document text
    • http://bloomx.com/sites/all/sites/bloomx.com/files/zonenafefuw.pdfIn PDF document text
    • https://ceadersvalet.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085820568484---mupizisubusuvebu.pdfIn PDF document text
    • https://kaptenhoki.info/contents//files/tejej.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_off0000f185.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF185 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010997.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10997 17168 bytes
SHA-256: 06e6cd42bc2b97999a6dbbbbdc498db61fdf62acbff8a3a2c7d1a815255c0698
font_02_sfnt_off0001369d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1369D 10712 bytes
SHA-256: 89292974b550440249ea723761a0304dd06c970e0f2f690382aa58cb90cd2ea2