Malicious PDF — malware analysis report

Static analysis result for SHA-256 51f0cbec09962003…

MALICIOUS

PDF

72.2 KB Created: 2021-10-07 18:25:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: e709cd0bb5c84571f64090113ac0041f SHA-1: 6a001b49f08ebaf5f3c559bdaf1bbb5492af6d6f SHA-256: 51f0cbec09962003e9b603e70481533847f8dfd850d040bf4ae10520855cfc3b
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, a common technique for executing malicious code within documents. It also features a link farm pointing to multiple compromised websites, including WordPress upload storage, suggesting an attempt to obscure the final malicious destination. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9915

Heuristics 7

  • 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.
  • 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://pixomot.ru/uplcv?utm_term=during+the+day+transpiration+and+photosynthesis+are+interlinked PDF link annotation
    • http://xn--c1aejbdnke.xn--p1ai/admin/ckfinder/userfiles/files/xutazi.pdfIn PDF document text
    • http://dyglas.com/userData/board/file/jovuwumafevimakiru.pdfIn PDF document text
    • http://artio.pl/files/files/59253855471.pdfIn PDF document text
    • https://www.tifdip.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614e56ab3a9ee---10724382369.pdfIn PDF document text
    • http://smarttechsolutionukltd.com/uploaded_files/userfiles/files/nomawegedepojufogi.pdfIn PDF document text
    • http://belniig.by/public/file/89059981226.pdfIn PDF document text
    • https://www.fibertech1.com/my_content/js/ckfinder/userfiles/files/genaxazokelomagozuxoda.pdfIn PDF document text
    • http://www.verneteco.com/ckfinder/userfiles/files/58768166779.pdfIn PDF document text
    • http://dobrasekacka.cz/userfiles/file/97858013757.pdfIn PDF document text
    • http://unite-chem.com/upload/files/wugagomokilu.pdfIn PDF document text
    • https://gz-topstar.com/wp-content/plugins/super-forms/uploads/php/files/a03714b661db27908f133b24adab2d17/69048511010.pdfIn PDF document text
    • https://fluffy-chins.com/images/file/kezifukuva.pdfIn PDF document text
    • http://xn--jt2b56wn0ap2a.com/upload/file/202109212327105565.pdfIn PDF document text
    • http://topoint.cc/userfiles/fckFile/20210919195653.pdfIn PDF document text
    • https://www.modianodesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b922c0e479---97369525213.pdfIn PDF document text
    • http://ktai.lmg.jp/upload/file/xunuguvakixofawod.pdfIn PDF document text
    • https://www.hdcorp.com.br/wp-content/plugins/super-forms/uploads/php/files/viv93q9qd2c29sfnutv3r2nrfs/1254782160.pdfIn PDF document text
    • http://www.zav-mito.si/wp-content/plugins/formcraft/file-upload/server/content/files/1612fa6c4dbc16---majalofebisexuximixeru.pdfIn PDF document text
    • http://viral-list-monster.com/ckfinder/userfiles/publics/files/72130250608.pdfIn PDF document text
    • http://sportschoolindex.nl/images/uploads/59136850428.pdfIn PDF document text
    • https://rentcar888.com/uploads/files/202109012118151342.pdfIn PDF document text
    • http://s-privod.ru/userfiles/file/witirofu.pdfIn PDF document text
    • http://chunmianxian.com/upfolder/e/files/20210923194654.pdfIn PDF document text
    • http://degeninhotel.ru/admin/ckfinder/userfiles/files/58086126524.pdfIn PDF document text
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/1333c8c73974cebbbfa65b8ecc8665a5/forifezijeledimuroj.pdfIn PDF document text
    • http://cukorbetegshop.hu/files/wujezubejejudoxoriro.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_off0000b9f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB9F5 10976 bytes
SHA-256: 237dd79c5a68f4a346ccf74f7b201b376e0375ab7a07e1e038a0d7386e98b528
font_01_sfnt_off0000d333.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD333 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000eb45.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB45 15544 bytes
SHA-256: 4c918db850b606c0342cc404fb1e107a2c533fd246778d61ebf89b24b11de631