Malicious PDF — malware analysis report

Static analysis result for SHA-256 6ee418c774dc9cca…

MALICIOUS

PDF

81.6 KB Created: 2021-09-16 12:46:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: dd0a6a8ef19323bb7d3d20ea385aa952 SHA-1: 340b938e7a4458f491e6dbc4c55fdbfa500058d1 SHA-256: 6ee418c774dc9ccae70ad89b65566b62ff8f8023fe67e2ebb4ef78342b0380c3
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV, with heuristics indicating a malformed exploit stream and a link farm pointing to compromised CMS uploads and disposable hosting. The document body, though heavily obfuscated, suggests it is a PDF generated by wkhtmltopdf, likely intended to host malicious links. The presence of numerous external URIs, many of which are PDFs themselves, reinforces the attack pattern of luring users to potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Malformed active-content stream length medium PDF_MALFORMED_EXPLOIT_STREAM_LENGTH
    A PDF stream that carries active/exploit-looking content has a declared /Length that does not match the recovered stream body. Malformed stream boundaries and length mismatches are common parser-evasion/supporting evidence around Reader exploit streams.
  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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=where%27s+my+widgets PDF link annotation
    • http://thetsaban3watnuea.com/UserFiles/file/luvabakiwezojinujotimoji.pdfIn PDF document text
    • http://phuongdonggolf.vn/app/webroot/uploads/files/wotojolimonaxujoguvukubox.pdfIn PDF document text
    • http://shamayachts.com/upload/file/13408931296.pdfIn PDF document text
    • http://104408017.linker.tw/files/gasupa.pdfIn PDF document text
    • https://helices-evra.com/userfiles/file/torelanutubuloz.pdfIn PDF document text
    • http://www.sm.ac.th/ckfinder/userfiles/files/nabefaropafojuv.pdfIn PDF document text
    • https://peterdegendt.be/file/mefure.pdfIn PDF document text
    • https://yodishit.com/uploads/userfiles/file/36817680587.pdfIn PDF document text
    • http://elitaliaweb.it/upload/file/67050357521.pdfIn PDF document text
    • http://ctkupavna.ru/upload/file/varobesoxipokivotuj.pdfIn PDF document text
    • http://abwvictory.com/uploads/files/widijogitalap.pdfIn PDF document text
    • http://piri-piri.pl/ckfinder/userfiles/files/93352775800.pdfIn PDF document text
    • https://suncables.co/images/file/83217397137.pdfIn PDF document text
    • http://milkexim.ru/imgeditor/file/96150908705.pdfIn PDF document text
    • http://foto-preiss.at/upload_files/files/gufox.pdfIn PDF document text
    • http://mineraux-et-lithotherapie.fr/ckeditor/upload/files/bufusomajuvetigiwepup.pdfIn PDF document text
    • https://trungtammatnamviet.vn/upload/files/63149434588.pdfIn PDF document text
    • https://earthchartercities.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613989690bced---bivetuvesovigafazub.pdfIn PDF document text
    • https://joyfool.art/wp-content/plugins/super-forms/uploads/php/files/bb28c4f8e4b9c7201ae80e5830e84681/legariwesotulur.pdfIn PDF document text
    • https://delaneyllc.com/ckfinder/userfiles/files/6244160376.pdfIn PDF document text
    • https://flylights.pl/wp-content/plugins/super-forms/uploads/php/files/d67727mu3bd869iu8rnobihr32/sinopalalanotex.pdfIn PDF document text
    • http://rwdwebwebdesign.com/img-aim/files/dezudopetububonerer.pdfIn PDF document text
    • https://samoinstitute.mn/uploads/assets/file/wijurikexuvex.pdfIn PDF document text
    • http://poiskvod.ru/images/file/50068896978.pdfIn PDF document text
    • http://stellarvvv.ru/ckfinder/userfiles/files/94421478518.pdfIn PDF document text
    • https://dcicz.org/userfiles/file/19845465961.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_off0000dd83.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD83 10488 bytes
SHA-256: 5396ad2b2e927cb25c537c343fa411c1ac29360ecc9ea3f554584935fee61e46
font_01_sfnt_off0000f54a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF54A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010d5c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D5C 16756 bytes
SHA-256: 93f6a27f9996fce324876cab09ea7ac9e5d43f9b682f02d9b8b2c37e9a63a95a

Open this report in the interactive analyzer, or submit your own file for analysis.