Malicious PDF — malware analysis report

Static analysis result for SHA-256 a424a0ed22235113…

MALICIOUS

PDF

80.8 KB Created: 2021-09-23 17:33:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 526f8503f9b727f70a18c65131ee54d4 SHA-1: b1863eb65b1fabbeb94e79343c73c42ae9faed2f SHA-256: a424a0ed22235113240f87766342de0b7722b2ec17a90a5c7a0f8c2114ae4ea3
172 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm for SEO poisoning or phishing. The ML classifier and ClamAV detection strongly suggest malicious intent. The embedded JavaScript likely facilitates the redirection to these malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 8

  • 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.
  • JavaScript action low 1 related finding PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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 http://sitoad.com/bbqjoekey/files/202109160412064726.pdf In PDF document text
    • http://subventionsbetrug.de/wp-content/plugins/super-forms/uploads/php/files/t7ihmbq1320lqtdhkav9p7032k/63322109039.pdfIn PDF document text
    • http://sake-tori.com/images/library/File/xoweralipibizetopokuv.pdfIn PDF document text
    • http://speckrepej.com/upload/file/vojurerumudapefuvos.pdfIn PDF document text
    • http://srihemkuntschoolint.com/slbdavbatala/userfiles/file/88824867903.pdfIn PDF document text
    • http://in-dapt.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132943ca2e5f---70882347505.pdfIn PDF document text
    • https://protum.se/file/57753273461.pdfIn PDF document text
    • https://brihat-group.com/assets/userfiles/files/nupetelaxufad.pdfIn PDF document text
    • http://lexus-custom.com/js/upload/files/nurudotijesojuzatevujuvej.pdfIn PDF document text
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/vp9q55vcpfllauan94cq24qri0/petivixopesosegosabamimof.pdfIn PDF document text
    • https://fablab808.com/nbloom/fckuploads/file/voregadaturejuwubiduba.pdfIn PDF document text
    • http://thanhtindesign.vn/uploads/image/files/fisebevijope.pdfIn PDF document text
    • http://tzsunup.com/upload/bepaguxif.pdfIn PDF document text
    • http://www.sudeshnamaulik.com/fckimages/file/bikofolevozugexizo.pdfIn PDF document text
    • http://dinhvi5s.com/images/newtech/files/618870265.pdfIn PDF document text
    • http://vzwsportenmuziek.com/content_docs/tebalureda.pdfIn PDF document text
    • http://sitarofindiamd.com/userfiles/file/jibipeno.pdfIn PDF document text
    • https://ksboutlet.com/file/files/legosa.pdfIn PDF document text
    • http://udelimpa.es/ckfinder/userfiles/files/51004287739.pdfIn PDF document text
    • http://bsp-plovdiv.org/ckfinder/userfiles/files/85941487862.pdfIn PDF document text
    • https://cdmsig2.com/ckfinder/userfiles/files/76809248016.pdfIn PDF document text
    • http://anhhieu.vn/hinhanh/file/wapopilugeju.pdfIn PDF document text
    • https://sacc-la-chaux-de-fonds.ch/fichiers/file/27333297660.pdfIn PDF document text
    • http://fundacjaproartis.pl/javascript/ckfinder/userfiles/files/luzumijepepobusaxewagis.pdfIn PDF document text
    • http://bennett-legal.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/32805490500.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=transfer+data+from+flip+phone+to+androidPDF link annotation
    • 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_off0000d993.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD993 16592 bytes
SHA-256: c8b4181e7f4205f8b507bb30cdc98e8bfe1ae356eb0d7ae18e7736f52bc70b1b
font_01_sfnt_off000104ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104AD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011cc4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CC4 10724 bytes
SHA-256: 6d178f3d4e094dc766860a87e21e790f65a2f09b128da07193c0ba1a78edbadd