Malicious PDF — malware analysis report

Static analysis result for SHA-256 cdc1361b99e75bf6…

MALICIOUS

PDF

85.5 KB Created: 2021-09-19 22:21:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 3a554b7cc3a4abb78aa7ce8deaf8fa33 SHA-1: b45d73824d60e7a2719fb55a669b6ce05488c675 SHA-256: cdc1361b99e75bf626c628ebfb9badaa277f1214375fa1f0d249408bd8a908c5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics as malicious, including a ML classifier and ClamAV, indicating it is likely a phishing or malware distribution lure. The heuristics 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' suggest the document contains a farm of links pointing to compromised or disposable hosting, designed to obscure the true malicious destination. While no scripts were explicitly extracted, the nature of PDF link farms often involves JavaScript for redirection or obfuscation, hence T1059.007 is included.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • 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.
  • 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://leresto-niort.fr/images/userfiles/files/fijuzoxoxegulaxizap.pdf In PDF document text
    • http://www.videocopilot.net/assets/public/ckfinder/userfiles/files/38278293184.pdfIn PDF document text
    • http://marketingnews.fr/images/file/govudeferavip.pdfIn PDF document text
    • http://radissonhoteltraining.com/userfiles/file/vovobatokafofunariwapur.pdfIn PDF document text
    • https://getracemirates.com/userfiles/files/2910577943.pdfIn PDF document text
    • http://styrexon.cz/userfiles/file/27487273879.pdfIn PDF document text
    • https://karpataljaturizmus.hu/upload/vuruzigafamolonekupaka.pdfIn PDF document text
    • https://hiperaktivite.info/userfiles/files/44099094218.pdfIn PDF document text
    • http://curry-box-deluxe.de/userfiles/file/23060569896.pdfIn PDF document text
    • http://mail-ex.net/userfiles/file/japarulexegigefomi.pdfIn PDF document text
    • https://okud-istra.hr/userfiles/file/vimujunigizowuvefevag.pdfIn PDF document text
    • http://jungam21.com/upfiles/file/1631843534.pdfIn PDF document text
    • https://siyata.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1613b4c1b4e9fe---34142139839.pdfIn PDF document text
    • http://msslink.ru/userfiles/files/11291555638.pdfIn PDF document text
    • https://anup.bo/images/files/dusawurimowabefafuz.pdfIn PDF document text
    • https://fereshtegan.net/basefile/fereshtegannet/files/98774982909.pdfIn PDF document text
    • https://calienglish.com/ckfinder/images_store/files/38277872682.pdfIn PDF document text
    • http://moveworldtogether.com/datas/files/sogorovubakijobowenegafi.pdfIn PDF document text
    • http://www.iqubz.com/wp-content/plugins/formcraft/file-upload/server/content/files/161417591f3288---96087685461.pdfIn PDF document text
    • http://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1614412933c007---nujobegovumijovuzivagupej.pdfIn PDF document text
    • https://www.ogblfrontaliers.fr/wp-content/plugins/super-forms/uploads/php/files/c141qgqcc8f37j7u0cote90cu8/xudobibetijogijezib.pdfIn PDF document text
    • https://ontogepszerviz.hu/editor_up/biberozugu.pdfIn PDF document text
    • http://www.nisbd.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139fe8949e7e---40505460512.pdfIn PDF document text
    • http://twozonechickenlasvegas.com/uploads/files/gexozej.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=delete+fingerprint+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_off0000e7fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7FA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010011.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10011 10504 bytes
SHA-256: a5cc1edb08736b313368ed389bea03ac3ff82fedf81eff40264288ac109e3f58
font_02_sfnt_off000117d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117D0 18820 bytes
SHA-256: 64c05974ec354bf15d5a16092038894483003101f937388ee2c1df437cd25752