Malicious PDF — malware analysis report

Static analysis result for SHA-256 573a39356d5223d4…

MALICIOUS

PDF

86.4 KB Created: 2021-10-08 16:38:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 22e7a6d5fea15c2d2c73b889251521cf SHA-1: 8e143a28c74ec1f3a0915e630bc7b55a14448dac SHA-256: 573a39356d5223d4b56720b4b3d4ddae93563ba969d990ef6a0b20d2f008ea0c
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which are part of a link farm hosted on compromised or disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The embedded JavaScript is a common technique for initiating malicious actions within PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://garglob.ru/uplcv?utm_term=extreme+edema+in+feet PDF link annotation
    • http://www.centrosanmarco.eu/img/news/files/81412421218.pdfIn PDF document text
    • https://silverbirdmarketing.com/pages/images/file/19837578679.pdfIn PDF document text
    • http://dmhu.eu/uploads/uplib/file/jatetuxomuwul.pdfIn PDF document text
    • http://gapp.fr/medias/files/82052059576.pdfIn PDF document text
    • https://cbolean.com/wp-content/plugins/super-forms/uploads/php/files/fa08b0a091ed22b0331a4d98b6ff3fe8/54346947381.pdfIn PDF document text
    • http://burattinojatek.hu/userfiles/file/26508137219.pdfIn PDF document text
    • http://mg001.cn/upload_fck/file/2021-9-11/20210911043834957886.pdfIn PDF document text
    • https://rowadalbyt.com/userfiles/files/37614448969.pdfIn PDF document text
    • http://studiosaletta.it/userfiles/files/76035400960.pdfIn PDF document text
    • http://lumieye.com/userData/ebizro_board/file/levobuto.pdfIn PDF document text
    • http://trenermichal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1615dfe328025e---19684981370.pdfIn PDF document text
    • http://gaudi.tw/upload/files/75781618860.pdfIn PDF document text
    • http://porpora.group/imagenes/imagenes_contenidos///38809397168.pdfIn PDF document text
    • https://cananalimdar.com/wp-content/plugins/super-forms/uploads/php/files/b387n3g6g04iabsu6986pd29ec/pelari.pdfIn PDF document text
    • http://sjar-tech.com/uploadfile/file///2021090322515820.pdfIn PDF document text
    • http://akvari-um.ru/userfiles/file/18740980174.pdfIn PDF document text
    • https://mercedesmazo.es/wp-content/plugins/formcraft/file-upload/server/content/files/1615bce1bc2ae3---70494058909.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/33571408064.pdfIn PDF document text
    • http://brickform.cz/obrazky/files/vawotulexumewomujep.pdfIn PDF document text
    • http://www.phsdcenter.com/temp/js/ckfinder/userfiles/files/dogabegoguloxemubavaz.pdfIn PDF document text
    • http://houtackers.nl/userfiles/file/6894078827.pdfIn PDF document text
    • http://asude.istanbul/ck_images/files/xasavixabafutaxijo.pdfIn PDF document text
    • http://ulv-fogger.ru/d/files/reteso.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_off0000eac4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAC4 10264 bytes
SHA-256: 0c30a402084ae4acb67fb9f9e4f99873feaab9f953eb5a28f03cf3aa565e0829
font_01_sfnt_off000101c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101C9 19964 bytes
SHA-256: 330a7c4bd5451e6bef4f3ea756e510e478a67020061e1d3415c082b1b27879df
font_02_sfnt_off00013478.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13478 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1