Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4a3f7a23090651e…

MALICIOUS

PDF

69.0 KB Created: 2021-09-24 23:11:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 38783fe645362ab2dcb5942557ccd7d3 SHA-1: 1c0cdd2eddf85024bb82835636666ccf97cf110e SHA-256: f4a3f7a23090651edbd2f3b248d25b277af0cdcf5a3de94035e8781aa5a2fcd8
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, indicating it is designed to redirect users to malicious websites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports the malicious nature by identifying a large number of links on disposable hosting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://inwebjor.ru/uplcv?utm_term=freddy+files+updated+edition+pdf PDF link annotation
    • http://miroslaws.com/ckfinder/userfiles/files/7482349229.pdfIn PDF document text
    • https://dom4m.de/userfiles/files/tofexevi.pdfIn PDF document text
    • http://apart1day.ru/file/dujegufawifokavotiteb.pdfIn PDF document text
    • https://gameadvisers.com/js/new/fckeditor/userfiles/file/55026876492.pdfIn PDF document text
    • http://hanaelectric.com/userData/board/file/71436545209.pdfIn PDF document text
    • http://wxmx.cn/upload/ckimg/files/202109230326112121.pdfIn PDF document text
    • http://maimungkorn.com/UserFiles/file/rukelajagafukovase.pdfIn PDF document text
    • http://suurelepa.ee/data/file/13421170181.pdfIn PDF document text
    • http://mn-lawfirm.com/box/userfiles/file/zobevum.pdfIn PDF document text
    • http://fujavietnam.com/images/Download/56809916984.pdfIn PDF document text
    • https://centrorevisionimonregalese.it/file/fejenuf.pdfIn PDF document text
    • http://movitecnic.com/ressource/site-image/files/2335574568.pdfIn PDF document text
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16148aa5a84745---biwawaditawagubapa.pdfIn PDF document text
    • http://www.terresdescaraibes.fr/file/mireruzemavumorarozizejuv.pdfIn PDF document text
    • http://jd6618.com/jd6618/file/2021-9/file/LwpCms2021_09_22_15_49_27_1087.pdfIn PDF document text
    • http://strap.sk/uploads/files/famoxoxex.pdfIn PDF document text
    • https://mygrind.ie/userfiles/file/95577435932.pdfIn PDF document text
    • https://dpengineers.info/admin/userfiles/file/bitomepojog.pdfIn PDF document text
    • http://fratellibeninca.com/images/file/89586021080.pdfIn PDF document text
    • http://wsmr.us/userfiles/file/xupujimulan.pdfIn PDF document text
    • https://bostoncake888.com/UserFiles/files/legeke.pdfIn PDF document text
    • https://coebmsf.com/userfiles/file/14611298362.pdfIn PDF document text
    • https://www.weldcor.ca/public/ckfinder/userfiles/files/88185274225.pdfIn PDF document text
    • http://tourgrodno.by/images/content/file/31233166389.pdfIn PDF document text
    • https://sarenpinler.com/calisma2/files/uploads/90010508775.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_off0000af18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF18 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c72f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC72F 10680 bytes
SHA-256: 447790635dd52d2e7daefee7452946dab93a390ee2e2ca72ac1255d0cb18999f
font_02_sfnt_off0000dfc5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFC5 15316 bytes
SHA-256: 344d71d21d13c931b01900445b44bb691385977935455b6d257c9b1ae2c95420