Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a75c793abc9cadf…

MALICIOUS

PDF

71.4 KB Created: 2021-09-16 21:51:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 8d4e9d77e3095d5ffcd01d5a12119047 SHA-1: 7f71adf139bd839c6815a043f4a6f558f60ab369 SHA-256: 4a75c793abc9cadf792f5dc4b2fd38c07060be44ed5f51f331a127f163465faf
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, indicating an attempt to redirect the user to malicious sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. The presence of embedded JavaScript points to its use as a delivery mechanism for further malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://nomylo.ru/uplcv?utm_term=portal+knights+apk+free PDF link annotation
    • http://lnaixi.com/userfiles/file/20210910215307_1640494325.pdfIn PDF document text
    • http://about-dogs.ru/upload/file/daverinifawevorafuvem.pdfIn PDF document text
    • http://centonze-vini.com/userfiles/files/7586296293.pdfIn PDF document text
    • https://cargotavio.ru/files/file/41714532744.pdfIn PDF document text
    • http://gima.ge/admin/ckeditor/ckfinder/userfiles/files/magosilotegabusawuz.pdfIn PDF document text
    • http://bagodilovaspark.hu/userfiles/file/tovifikito.pdfIn PDF document text
    • http://flairpens.ru/uploads/file/ruzulofuvuv.pdfIn PDF document text
    • https://fengshan-zhennangong.org/upload/ckfinder/files/35783322015.pdfIn PDF document text
    • http://wasserentkalkung.at/ckfinder/userfiles/files/wiwitosulawefiruvaw.pdfIn PDF document text
    • http://exhibitionchannel.com/upload/gutowalemimezuxonuziju.pdfIn PDF document text
    • http://garage-ys.info/js/upload/files/jofupavepatavolos.pdfIn PDF document text
    • http://thegrcinstitute.org/app/webroot/js/ckfinder/userfiles/files/kinunizubusigunado.pdfIn PDF document text
    • https://fmpride.com/wp-content/plugins/super-forms/uploads/php/files/d9658665a28e5a0b2f86110b92d8ead1/58946901148.pdfIn PDF document text
    • http://eastendmediation.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/6669369838.pdfIn PDF document text
    • https://m-astar.com/UserFiles/files/68514648921.pdfIn PDF document text
    • http://thangmayedex.com/webroot/img/files/vumekafulovexadejemut.pdfIn PDF document text
    • http://ha-sine.com/d/files/bavijowuri.pdfIn PDF document text
    • https://tenshinorchids.com/FCKeditor_upload/file/wipufaxoje.pdfIn PDF document text
    • https://briljant-maleri.se/UserFiles/files/gimabopepodutobodub.pdfIn PDF document text
    • https://gkatsov.com/userfiles/file/befajobav.pdfIn PDF document text
    • https://keyword-lda.pt/site/upload/file/61831765016.pdfIn PDF document text
    • http://imagespa.mx/wp-content/plugins/formcraft/file-upload/server/content/files/16140bc657ca56---13395163589.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/1613c8f3e8a472---bugafopizokegorifodenaza.pdfIn PDF document text
    • http://perchegouet.com/ckfinder/userfiles/files/88790680333.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_off0000b2db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB2DB 10728 bytes
SHA-256: 48363c4495779090985aa14c9c3a9bd52e19475550edd0ab190ecd24c1883217
font_01_sfnt_off0000cb76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB76 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e388.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE388 18188 bytes
SHA-256: 0c4963eb389daea65c536c13a814d58e0b6f4c460a89d3b7f14be4d414547d52