Malicious PDF — malware analysis report

Static analysis result for SHA-256 6c4c8756f6186d8b…

MALICIOUS

PDF

89.0 KB Created: 2021-06-27 04:29:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c40fc41b61cb55ef5fb8c0b1b6c0d820 SHA-1: 8849dc1abff8b6eb49544191e6e6e00ec7db9c74 SHA-256: 6c4c8756f6186d8b990a61b09826e936456969e899c905e09c5124bf63d7f922
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous external URIs and links to compromised WordPress upload storage, suggesting it functions as a link farm designed to redirect users to potentially harmful websites. The presence of multiple compromised or disposable hosting links reinforces the phishing or malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://ketchas.ru/uplcv?utm_term=inclined+to+say
    • https://muguet.fr/sites/default/files/file/nirogikeloloniravimoku.pdf
    • http://dragonera.cn/admin/userfiles/file/72496732050.pdf
    • http://cga82.com/admin/File/robuvimul.pdf
    • http://dgjinhak.kr/DATA/upload/files/202106081204358512.pdf
    • http://tamker.hu/userfiles/file/jewopexoviwobaxez.pdf
    • http://giaoducvietnamtv.com/images/ckeditor/files/vadirujokado.pdf
    • http://historia-bfured.hu/userfiles/file/zujaratojewudelaretaxani.pdf
    • https://hosvagyok.hu/userfiles/file/83721839428.pdf
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/160948b3962854---98037782943.pdf
    • https://booknowrentalimo.ch/userfiles/files/22246830377.pdf
    • http://taiwanglassgroup.cn/userfiles/file/nuzugiwuwejizirig.pdf
    • https://xn--80adj7cxa.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/f76cea0e7c458a6668c2fbd56e809bba/welexagipulilopowu.pdf
    • https://belhasasecurity.com/userfiles/file/83030945815.pdf
    • http://aksaxena.com/bpms/includes/fckeditor_uploads/userfiles/file/baxuxepexikujawunu.pdf
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/78p8he48du6qp18v592plae5ss/11644778007.pdf
    • http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/1608296e2db204---80541937429.pdf
    • http://mesotects.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607250d135145---92944600911.pdf
    • http://www.farparts.cl/wp-content/plugins/formcraft/file-upload/server/content/files/16079626d8cd2e---xofizanepegogeforosopusus.pdf
    • http://boathousebrokerage.com/userfiles/file/vuvafa.pdf
    • https://cbdc.co/uploads/ckfinder/userfiles/files/mumidazeju.pdf
    • https://3dreamstudios.com/wp-content/plugins/super-forms/uploads/php/files/0b1092cdba0cda1872dbd913f2d1cc69/bizukijotokewas.pdf
    • https://www.americanapi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c301f0c68e1---basimusalukedonabobeja.pdf
    • https://zahnersatz.pl/userfiles/files/36845455414.pdf
    • https://refour.eu/wp-content/plugins/super-forms/uploads/php/files/4e06b2df336db11259e0ec0ce7555232/39432285540.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fada.bin
e187594f246ddde50722588f255798219623bb3a10d42fb4faf50fdb5d8bb907
pdf-font-stream PDF embedded font (sfnt) at offset 0xFADA 17080 bytes
font_01_sfnt_off00012792.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12792 16792 bytes
font_02_sfnt_off00013fa9.bin
da0a4406ced8b693165fccdae50607575942aa7cba70349bf98e3102f4010585
pdf-font-stream PDF embedded font (sfnt) at offset 0x13FA9 10328 bytes