Malicious PDF — malware analysis report

Static analysis result for SHA-256 df19c9066b8fa26a…

MALICIOUS

PDF

70.0 KB Created: 2021-09-30 14:52:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 802c096ae36ff9128c73f452739b545e SHA-1: 77c65ea15b5b8806a6abdfcea599d4b2747a4e81 SHA-256: df19c9066b8fa26a4e400a36c9a9165e8ab7bc7f2558cf82b8587c18faee751b
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a significant number of external URIs, many of which are hosted on compromised CMS upload directories or disposable hosting. These links form a link farm, likely intended to redirect users to phishing sites or download further malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://infrive.ru/uplcv?utm_term=toefl+reading+practice+book+pdf PDF link annotation
    • https://www.hospedeagora.com.br/wp-content/plugins/super-forms/uploads/php/files/hhphlo35i2j8au8hgvlnpu3fvm/bixasumilatebejazu.pdfIn PDF document text
    • http://onmamtour.com/FileData/ckfinder/files/20210925_79FEBA703A4F1386.pdfIn PDF document text
    • http://we2meeting.com/ckfinder/userfiles/publics/files/82219203989.pdfIn PDF document text
    • http://nj-rshb.com/v15/Upload/file/20219822385853.pdfIn PDF document text
    • https://savitravel.ro/ckfinder/userfiles/files/41027991433.pdfIn PDF document text
    • http://vinhthuan.vn/upload/files/30592901162.pdfIn PDF document text
    • https://www.vibrationmonitoring.asia/wp-content/plugins/formcraft/file-upload/server/content/files/16145c27bd420c---13569951313.pdfIn PDF document text
    • https://playgametoday.ru/wp-content/plugins/super-forms/uploads/php/files/4ffa78d37932a4d1dda611f5bd45435f/72675385071.pdfIn PDF document text
    • http://emusicmarket.com/upfile/board/files/79849722129.pdfIn PDF document text
    • https://fereshtegan.net/basefile/fereshtegannet/files/85699798698.pdfIn PDF document text
    • https://butagallery.com/userfiles/files/foniwusen.pdfIn PDF document text
    • http://an-professional.ru/img/files/file/12244976338.pdfIn PDF document text
    • http://thermogroup.ru/uploads/files/kanopuwesafulozinosoguxex.pdfIn PDF document text
    • http://zzzwchem.com/upload/files/4727862486.pdfIn PDF document text
    • http://mega-stainlesssteel.com/uploads/image/files/38199546664.pdfIn PDF document text
    • https://jechrina.gr/FCKeditor/userimages/file/fizorimulali.pdfIn PDF document text
    • http://perechen-jurnalov.ru/js/ckfinder/userfiles/files/wutebovotubajulawi.pdfIn PDF document text
    • http://speaklifeiamgreatness.com/files/files/xulife.pdfIn PDF document text
    • https://drainscovers.com/wp-content/plugins/super-forms/uploads/php/files/3b9d9bee652c207895676dc4373953c9/kemajizizunelenozinimema.pdfIn PDF document text
    • https://www.cifphosteleriayturismo.es/ckfinder/userfiles/files/lewabuwufunudakutegib.pdfIn PDF document text
    • https://ivfnna.gr/wp-content/plugins/super-forms/uploads/php/files/7dd7a1fec1876f594ba154f1386d4324/wiwafasogipawuwusapuran.pdfIn PDF document text
    • https://pierrelemagicien.com/userfiles/file/gulazure.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_off0000b085.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB085 16748 bytes
SHA-256: 9ad1cfacc1be41c70be05c173555265453b24561251c5df3102add6d6b7c44c7
font_01_sfnt_off0000d9b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9B5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f1cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1CC 10824 bytes
SHA-256: e42e967415173bb4c6bbcc3361204ae412196f3c9ba155797750d89ac18dac57