Malicious PDF — malware analysis report

Static analysis result for SHA-256 fe98f99557ffd843…

MALICIOUS

PDF

87.3 KB Created: 2021-09-13 05:25:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 69c51d50838f2da15150ac03185bb940 SHA-1: be08a9fb39dfdc7899ecf049ff215175ca14a7dd SHA-256: fe98f99557ffd843d0286e13e8e5c46c9f72fafbabbf555da142db83ede2e7b8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external websites hosted on potentially compromised or disposable domains. The presence of numerous URLs, many with 'utm_term' parameters, suggests an attempt to manipulate search engine results or phish users by luring them to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://nomylo.ru/uplcv?utm_term=allwinner+a13+tablet PDF link annotation
    • http://macabrey-luthier.fr/data/Files/62364761742.pdfIn PDF document text
    • http://a-pluset.com/userfiles/podaniraverixobuw.pdfIn PDF document text
    • http://basse-normandie.annuaire-regional.com/ckfinder/userfiles/files/kareridamegezilo.pdfIn PDF document text
    • http://zavalinka.by/var/upload/file/16347261783.pdfIn PDF document text
    • http://turar-mussin.com/userfiles/File/56043170883.pdfIn PDF document text
    • http://thanuyentea.com/ckfinder/userfiles/files/51798374327.pdfIn PDF document text
    • https://ahl2005.com/ckfinder/userfiles/files/8864860660.pdfIn PDF document text
    • https://sharzh-ufa.ru/wp-content/plugins/super-forms/uploads/php/files/da09cf001623c53c08e15bbc1afa450e/vogazerinef.pdfIn PDF document text
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bbce54e339---kasikibit.pdfIn PDF document text
    • https://nyirfa.hu/uploads/files/fikeloruv.pdfIn PDF document text
    • http://aatmicscience.org/asuserfiles/file/rewininale.pdfIn PDF document text
    • http://broadviewlibrary.org/uploaded_bvlib/file/digazidalaxajokinolewesij.pdfIn PDF document text
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136f39489f96---gubawitijeborusanibisuxi.pdfIn PDF document text
    • https://inlandautorepairmurrietaca.com/wp-content/plugins/super-forms/uploads/php/files/df534e5ba048d3975ba405c2a0c42ce9/83318691854.pdfIn PDF document text
    • http://michardardillier.com/ckfinder/userfiles/files/terada.pdfIn PDF document text
    • http://anpharma.net/upload/files/17328860228.pdfIn PDF document text
    • https://www.tctnanotech.com/wp-content/plugins/super-forms/uploads/php/files/d88f1bf03346493545496a825bc5fa42/76488067145.pdfIn PDF document text
    • https://wroclawmodelshow.pl/ckfinder/userfiles/files/mudulofejibudelemifewo.pdfIn PDF document text
    • http://w-f-l.de/user_img/file/20447294992.pdfIn PDF document text
    • http://ylphs.com/ckfinder/userfiles/files/55063550074.pdfIn PDF document text
    • https://maximatrimony.com/ckfinder/userfiles/files/3611557179.pdfIn PDF document text
    • http://klubbelgickychobrov.sk/editor_uploads/files/8377434694.pdfIn PDF document text
    • http://stellarp.com/userfiles/file/23390658494.pdfIn PDF document text
    • http://dabaizhongxue.com/upload_fck/file/2021-9-8/20210908110209957386.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_off0000e87a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE87A 21184 bytes
SHA-256: de5b3df36d6c596d8159c156a9322cfd37741bf4f281f70ed4f0852a9df39863
font_01_sfnt_off0001209e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1209E 10244 bytes
SHA-256: 4f974db15a187e1484a681ff4a0a4627f6496af3115adf6b5157f75205b3f7dd
font_02_sfnt_off000137e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x137E4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1