Malicious PDF — malware analysis report

Static analysis result for SHA-256 335b11e3bb246022…

MALICIOUS

PDF

68.9 KB Created: 2021-10-02 15:05:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 3fb2283d0213e236100b273ae639fa22 SHA-1: d153598173b54edca48bbe99278d94a63e6dc1e5 SHA-256: 335b11e3bb24602275b203f4fc0909e0586a451a7a4944a3f1edf8840bcdb5ee
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file containing embedded JavaScript, which is a common technique for executing malicious code. It also features a large number of external links, many pointing to other PDF files hosted on various domains, suggesting a link farm or redirection mechanism. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://allytemp.ru/uplcv?utm_term=is+huntington%27s+dominant+or+recessive PDF link annotation
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/16149160930120---fobipe.pdfIn PDF document text
    • http://dui-antidote.net/images/userfiles/file/sujetufof.pdfIn PDF document text
    • http://landonintergroup.com/ckfinder/userfiles/files/fejufegijerijidi.pdfIn PDF document text
    • http://euroteam.vn/ckfinder/userfiles/files/97314609992.pdfIn PDF document text
    • https://clicksnepal.grnca.org/img/files/files/wopusanonejo.pdfIn PDF document text
    • http://teen.plovdivweek.com/js/ckfinder/userfiles/files/47455316154.pdfIn PDF document text
    • http://ukrainski-rosyjski.pl/userfiles/file/97468492497.pdfIn PDF document text
    • https://rotterdampools.com/contents/files/vofojomefete.pdfIn PDF document text
    • https://argumentua.com/i/file/zozajewuligawulazomam.pdfIn PDF document text
    • http://gesht.ru/admin/ckfinder/userfiles/files/84132628706.pdfIn PDF document text
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/ogrh14vvlha4bmlpr78ku96rno/52733853137.pdfIn PDF document text
    • http://www.oneworldkarate.com/fckeditorimages/userfiles/file/82652960150.pdfIn PDF document text
    • http://classtool.info/upload/files/95715178798.pdfIn PDF document text
    • http://lammermoor.net/imagenes/file/1395618061.pdfIn PDF document text
    • https://www.truckersplantparts.co.uk/ckfinder/userfiles/files/beguvipaliraxakuzomuwisop.pdfIn PDF document text
    • http://balatonfurediallatorvos.hu/userfiles/file/xunubozomufogufuwaxibudo.pdfIn PDF document text
    • http://mojahotels.com/ckfinder/userfiles/files/39474350782.pdfIn PDF document text
    • http://sinners-party.de/media/file/bofapatet.pdfIn PDF document text
    • https://wamsconference.com/wp-content/plugins/super-forms/uploads/php/files/605f0229f0d9aaf8b152d4534042d026/60154505969.pdfIn PDF document text
    • https://dcoderesearch.com/uploads/lovonunowuvix.pdfIn PDF document text
    • http://www.viksexteriors.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139484f8564f---52389048045.pdfIn PDF document text
    • https://armour-technoz-ca.otzol.net/ckfinder/userfiles/files/wuxav.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_off0000ae89.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAE89 10920 bytes
SHA-256: 0b9592674e7962c4d218e5bd48a128870208c3e24f5defbb616e85ac4b0a1991
font_01_sfnt_off0000c77e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC77E 15480 bytes
SHA-256: fd10f007193148b4610e9d17d8aca62c6b2de907af9ea6cbb472ff95ee184004
font_02_sfnt_off0000ee11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE11 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1