Malicious PDF — malware analysis report

Static analysis result for SHA-256 f520b070173041ad…

MALICIOUS

PDF

80.3 KB Created: 2021-09-16 12:21:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 066e03043359fba6d0ab7d073703d840 SHA-1: a5d8925cf0768cd2670bf57b816233259a9caa15 SHA-256: f520b070173041ad7b3826e0a138f235525762eefa767fde236f3c71acc98ca4
164 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious. It contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically indicates this behavior.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://vincityhomes.vn/wp-content/plugins/super-forms/uploads/php/files/d8u80crl8i07k89aq2712ki46m/jopofuxowegiwakokexodibev.pdf In PDF document text
    • http://fluitec.fr/ressource/site-image/files/jetopej.pdfIn PDF document text
    • http://baraanduliaptti.org/userfiles/file/tevelijiwomonezokupe.pdfIn PDF document text
    • http://csc021.com/userfiles/file/20210914115043_un4yhg.pdfIn PDF document text
    • https://thebottombillion.org/business_school/uploads/file/sasolewikokowukoxodudofun.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/1a44b0cc5f9d04b630ae32fb933f6dff/23133169490.pdfIn PDF document text
    • http://chulatutoracademy.com/chulatutor/ckfinder/userfiles/files/33132135944.pdfIn PDF document text
    • http://xn--b1adrijbbb.xn--p1ai/upload_picture/tavexebe.pdfIn PDF document text
    • http://otvorene-srdce.sk/userfiles/file/tititemizemeletojazar.pdfIn PDF document text
    • http://videlec.be/ressource/file/tuninefulitojuxaneg.pdfIn PDF document text
    • http://auroraenergyproject.it/userfiles/files/sazegiwuwafafiwegeniga.pdfIn PDF document text
    • https://shivajigrihnirman.com/singhania/downloads/file/buzulekisije.pdfIn PDF document text
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138792691142---52740322789.pdfIn PDF document text
    • http://6nergy.fr/6nergy/sites/default/user/file/fulejavuzegigixipiwebo.pdfIn PDF document text
    • http://anaminfo.com/attachfile/file/82728445504.pdfIn PDF document text
    • https://holzhaus-suedtirol.it/wp-content/plugins/formcraft/file-upload/server/content/files/16136713bd0ebc---terofefaga.pdfIn PDF document text
    • http://wwm-quanta.com/upload/files/82896725857.pdfIn PDF document text
    • http://keralastatetailorsassociation.com/userfiles/file/lezom.pdfIn PDF document text
    • https://ivanamihic.com/files/17467446694.pdfIn PDF document text
    • http://matchedtubes.de/userfiles/file/5331039407.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=genshin+impact+live+wallpaper+ipadPDF 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_off0000d21b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD21B 10852 bytes
SHA-256: 5ca291eb0e1e3ccd04d2df5bf604484a3cfdb6c313b727070cbdd1c8c1196c62
font_01_sfnt_off0000eb08.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB08 18496 bytes
SHA-256: b5c0f3aaf384505016f228f7b2fdf455bb294cf2840bc0eebc80f0107a9f4222
font_02_sfnt_off00011bdf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BDF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1