Malicious PDF — malware analysis report

Static analysis result for SHA-256 86e833055e6a1c0c…

MALICIOUS

PDF

82.1 KB Created: 2021-09-21 19:10:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 18b78131ea552c8785c855aed3f0c28b SHA-1: 28a7d0059739816ce626d3db810a2d88c37fbed3 SHA-256: 86e833055e6a1c0c6d72018d5b6945ddb342e6924e7fdc2c58d83dcc1de97750
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code within documents. Additionally, numerous URLs were extracted, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier further support the malicious nature of this file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://cructi.ru/uplcv?utm_term=how+to+enable+usb+otg+on+android+devices PDF link annotation
    • https://www.olympusnorge.no/wp-content/plugins/super-forms/uploads/php/files/fhqms60ftjca2mleh52bi3ffbl/zatelisaberalatatejup.pdfIn PDF document text
    • https://tiklatakip.com/calisma2/files/uploads/98074345251.pdfIn PDF document text
    • http://nattukoottam.com/userfiles/file/23532396301.pdfIn PDF document text
    • http://web-news.eu/www/pkpar/userfiles/file/lusis.pdfIn PDF document text
    • https://globalybm.com/ckfinder/userfiles/files/1630506967.pdfIn PDF document text
    • https://www.ibyservice.com/wp-content/plugins/super-forms/uploads/php/files/874fd66afe66f1263908377542dbe136/69962370417.pdfIn PDF document text
    • http://haiqi-machine.com/d/files/nonamebemaxabisesifikef.pdfIn PDF document text
    • http://ooexperience.be/assets/Image/files/35556797499.pdfIn PDF document text
    • http://ccsup.co.th/uploads/ckfinder/files/22870757225.pdfIn PDF document text
    • https://ptkas.com/kingkong/userfiles/files/28213849732.pdfIn PDF document text
    • https://journeywithmypet.com/ckfinder/userfiles/files/pesewavisi.pdfIn PDF document text
    • http://xn--80aantfcaehjbxzf1m.xn--p1ai/userfiles/file/35794249181.pdfIn PDF document text
    • http://grandviewgroupresort.com/upload/files/49528004313.pdfIn PDF document text
    • https://u-spot.biz/js/ckfinder/userfiles/files/jebulopukobabuluxoma.pdfIn PDF document text
    • http://eugensa.lt/app/webroot/uploads/userfiles/files/rebosezoremejatotet.pdfIn PDF document text
    • https://metroguards.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613d31a10a68d---mevawimu.pdfIn PDF document text
    • https://lawweb.info/mycms/admin/userfiles/file/4319361250.pdfIn PDF document text
    • http://jrpst.pl/userfiles/file/govunu.pdfIn PDF document text
    • http://tutek.eu/userfiles/file/bupakajigekopizozewimagek.pdfIn PDF document text
    • http://lionsmarsala.it/userfiles/files/firiwowajugenos.pdfIn PDF document text
    • https://acethamessecurity.co.uk/wp-content/plugins/super-forms/uploads/php/files/c9526c7913bd30a727650202a09260a1/vikatijezigofidodagu.pdfIn PDF document text
    • http://xhiehchin.com/Xhieh_News/_file/73029457561.pdfIn PDF document text
    • http://sdhmladavozice.cz/userfiles/file/7468993012.pdfIn PDF document text
    • https://12shio4.com/contents/files/10677245755.pdfIn PDF document text
    • https://twinslock.com/locktactyuma/userfiles/file/bakazelikejufa.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_off0000d87e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD87E 18744 bytes
SHA-256: b47f3e900b7b207b396f10e3c5bfb9fc0cde359ff573566ebec6017ee0ef66c5
font_01_sfnt_off0001090f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1090F 10928 bytes
SHA-256: 00ed0d2be5c251fd15d6339d783e8be2ea7ca6fd88fae6f8f58a8eeeeb1f624d
font_02_sfnt_off00012257.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12257 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1