Malicious PDF — malware analysis report

Static analysis result for SHA-256 f094427a2f8b5588…

MALICIOUS

PDF

78.0 KB Created: 2021-08-29 12:48:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-01
MD5: 1ae2bf75c81a8e8d2785b66ffdf22d19 SHA-1: 2bf1e9d52001eb95d6c4f0467f5e6885461c13e7 SHA-256: f094427a2f8b5588f023888754851b65622520efd66be07c24e0e1326437a4f9
204 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and contains embedded JavaScript. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9885

Heuristics 8

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://prestinireedcorp.com/userfiles/files/vatujafiwud.pdf In PDF document text
    • https://groupunsur4.com/contents//files/59933228623.pdfIn PDF document text
    • http://xn--dlek-5qa.com/admin/UserFiles/file/sikudov.pdfIn PDF document text
    • https://c4ir.ae/wp-content/plugins/super-forms/uploads/php/files/5iaiq3ft4b1akg1vo90s0ulro5/39338446609.pdfIn PDF document text
    • http://barrarioservicos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609378ca4fdaf---satelizawok.pdfIn PDF document text
    • http://velo.hu/UserFiles//file/vovimonakewuzidopolutogob.pdfIn PDF document text
    • https://ccveg.org/wp-content/plugins/super-forms/uploads/php/files/4nh2ljfakron9hj5r1mhtjrkk3/zabiwevufer.pdfIn PDF document text
    • http://wsystem.sk/userfiles/files/54196568305.pdfIn PDF document text
    • http://markone-tools.com/upload/files/rutonoferexoxazoz.pdfIn PDF document text
    • https://www.schroedersales.com/wp-content/plugins/super-forms/uploads/php/files/486288bee1dd6a78873ff69f39e48939/xosesunaveda.pdfIn PDF document text
    • https://pakistanchristiancongress.org/userfiles/file/3583622391.pdfIn PDF document text
    • http://www.phsdcenter.com/temp/js/ckfinder/userfiles/files/pigagadidogawodipomur.pdfIn PDF document text
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611ad99b7791a---fetugemafonamep.pdfIn PDF document text
    • http://ckattorneys.net/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/6047240509.pdfIn PDF document text
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2239f126b5---5591599849.pdfIn PDF document text
    • http://sakirnoopo.ru/wp-content/plugins/super-forms/uploads/php/files/f45072250b285c13ba961f6f5e158618/nazufolutikitatoxid.pdfIn PDF document text
    • http://farashimirooz.com/files/86121767569.pdfIn PDF document text
    • https://www.carnesvarejo.com.br/assets/ckfinder/core/connector/php/uploads/files/todurijirigujinuwuku.pdfIn PDF document text
    • http://www.hkqi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0e92e514df---titebum.pdfIn PDF document text
    • http://sabaispa.net/userfiles/file/8083143534.pdfIn PDF document text
    • http://doublehappyvstheinfinitesadness.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a43e81a2b85---taretasinowiwunasejaf.pdfIn PDF document text
    • https://thefertilizerequipment.com/d/files/59084003326.pdfIn PDF document text
    • http://berrybucs1973.com/clients/3/3a/3a2d6910be1067feaf6dc79f90d505e0/File/ladezonenipus.pdfIn PDF document text
    • https://altonika.pro/files/fck/file/63829069273.pdfIn PDF document text
    • http://agcslohian.com/userfiles/file/marovoxaxuluju.pdfIn PDF document text
    • https://beysukonaklari.com/ckfinder/userfiles/files/10401833221.pdfIn PDF document text
    • http://beijinghuojia.cn/userfiles/file/14571494119.pdfIn PDF document text
    • http://vallovin.it/userfiles/files/zunerujuja.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=important+reagents+in+organic+chemistry+for+jee+mainsPDF 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_off0000c9ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9EA 17352 bytes
SHA-256: dbe4d6642ff269be341e4decc8488b9a69c3293c7f867c59bcab7a4be1f958b6
font_01_sfnt_off0000f678.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF678 11076 bytes
SHA-256: bd37e678e9ae1eccea700271beb1f05b5ead39ae9fa5292f10b5c8ce655b7804
font_02_sfnt_off00011017.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11017 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1