Malicious PDF — malware analysis report

Static analysis result for SHA-256 4caf6c37a5c57c77…

MALICIOUS

PDF

88.7 KB Created: 2021-08-14 19:18:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 85f91571bff5fe3623f52998f0339a6a SHA-1: b435dec977484d6fee85e96e27a6c859c7d579e4 SHA-256: 4caf6c37a5c57c77b0b2a0a920be7eff3ff922e9bcf329ca935426a8afeaa580
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF contains embedded JavaScript and a large number of URLs, many of which point to compromised websites or disposable hosting, forming a link farm. The embedded JavaScript is likely used to facilitate the redirection to these malicious URLs, which are designed to lure users into downloading further malware or providing sensitive information. The ClamAV detection and ML classifier strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://archism.ru/uplcv?utm_term=perricone+28+day+diet+pdf PDF link annotation
    • https://big-cash.de/wp-content/plugins/super-forms/uploads/php/files/si0vduqrk8hth25gchbvpnhvgv/nuwisirazebokux.pdfIn PDF document text
    • https://landbar.com/upload/files/95567668257.pdfIn PDF document text
    • https://feng-shuiworld.com/userfiles/file/86109598527.pdfIn PDF document text
    • http://princeworldwide.com/multimedia/userfiles/file/pajed.pdfIn PDF document text
    • http://benhvienlaptop.biz/userfiles/file/31510797403.pdfIn PDF document text
    • http://sinara.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b4da90e8217---fubidikatawojaletikusu.pdfIn PDF document text
    • https://completecollegestrategies.com/wp-content/plugins/super-forms/uploads/php/files/ebf81bc032dfdb27088df873ff899deb/26547310917.pdfIn PDF document text
    • https://cashofferoregon.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2f2a41f7c4---wuvupe.pdfIn PDF document text
    • http://pmdrecycling.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a8b2864858---delutokepafol.pdfIn PDF document text
    • http://salinahighschool1968.com/clients/3/33/33fcb9b832a528c934b1ac42c6b88a99/File/3040549280.pdfIn PDF document text
    • http://www.jcca.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/160e97f1af133a---surovipatekasudarirodobot.pdfIn PDF document text
    • https://maplesservice.com/wp-content/plugins/super-forms/uploads/php/files/ec29c40cc42e9e21f6489d94ca6e24f2/tewukonawikikaxubetir.pdfIn PDF document text
    • http://anhuicrew.com/upload_fck/file/2021-5-23/20210523132220752564.pdfIn PDF document text
    • http://auchli-appenzeller.ch/userfiles/files/gedijukaba.pdfIn PDF document text
    • https://ltssinternational.com/res/wysiwyg/file/nokagatefegumazu.pdfIn PDF document text
    • http://zerosquareonline.com/file/fexujefofup.pdfIn PDF document text
    • https://teenvolunteerdallas.org/wp-content/plugins/super-forms/uploads/php/files/a71664725e6c7a53ac92fde617248feb/nukavonekojuti.pdfIn PDF document text
    • https://www.bankkartya.hu/js/ckfinder/userfiles/files/gaberis.pdfIn PDF document text
    • http://www.esthemed.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160bec075ec8d3---zapub.pdfIn PDF document text
    • https://higher-reason.com/wp-content/plugins/super-forms/uploads/php/files/mqu4dkil9h4tnsu2jfj3nsqv33/29164067432.pdfIn PDF document text
    • https://smoothnomad.com/wp-content/plugins/super-forms/uploads/php/files/19gngeb8m0uue39hobtj7om25k/zejotasedesanip.pdfIn PDF document text
    • https://bestofbucerias.com/upload/file/detub.pdfIn PDF document text
    • http://ahkjt.com/upfile/file/92697444719.pdfIn PDF document text
    • http://www.sarajevo-inn-grunewald.com/wp-content/plugins/formcraft/file-upload/server/content/files/160afe33fb38c7---guxekadip.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_off0000f788.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF788 10840 bytes
SHA-256: 41e471c6a4cabc19b0251e72a0861ee7b471009243fe294c07ce987de30a704b
font_01_sfnt_off000110c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110C9 16652 bytes
SHA-256: 656679eb4f4e18f0996ef6305888cedc7eedb0d11d41e5bbe908daa20f354547
font_02_sfnt_off00013bba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13BBA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1