Malicious PDF — malware analysis report

Static analysis result for SHA-256 fc647089b9109b55…

MALICIOUS

PDF

75.1 KB Created: 2021-08-28 19:44:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 3e188d2476e9cbb55e5b3253e8f6657f SHA-1: c74c1203394a4e43403beda3452361a995b0ea04 SHA-256: fc647089b9109b55f4c4ee2d60a69d4dd89c6b0c2ed1aed545736e9bf71f7a9b
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains a large number of external links, many pointing to compromised or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, providing no direct user-facing content but likely serving as a container for the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://bigband-ulm.de/userfiles/files/6248324121.pdf In PDF document text
    • https://alexandrapanayotou.com/web/images/static/file/sosunelepipi.pdfIn PDF document text
    • http://vincityhomes.vn/wp-content/plugins/super-forms/uploads/php/files/mkttaoa4q0bbsj8b5030p3dq01/dadunip.pdfIn PDF document text
    • https://a-pointpro.com/cms/ckfinder/userfiles/files/vuligumegarujaso.pdfIn PDF document text
    • https://40parables.com/wp-content/plugins/super-forms/uploads/php/files/27190cb1d71e959fa8a13b337348bf5c/68338704029.pdfIn PDF document text
    • http://artospace.com/pics/file/napugaruwepolimiboj.pdfIn PDF document text
    • http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608d1cf746bc2---5692287198.pdfIn PDF document text
    • https://robertmatzuzi-massagetherapist.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160afb6a8ba525---nodosifowasetijosa.pdfIn PDF document text
    • http://caacoding.net/wp-content/plugins/formcraft/file-upload/server/content/files/160fea9af3c0a2---jorilaxavumodapikiw.pdfIn PDF document text
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/bca1f47eacc044478a8aee977e5dbc3a/wufuwuguf.pdfIn PDF document text
    • https://prana.video/wp-content/plugins/super-forms/uploads/php/files/ukgdm1pn86hi5oto6hdgkpmqvp/31329172229.pdfIn PDF document text
    • http://scro.ru/pic/file/fibatonir.pdfIn PDF document text
    • https://homeaestheticsllc.com/wp-content/plugins/super-forms/uploads/php/files/2285c26612a59ba38127f5d3dbb8485e/jojanarosabakukisi.pdfIn PDF document text
    • http://mfplus.ba/wp-content/plugins/formcraft/file-upload/server/content/files/1606f689b2e4ba---87025123287.pdfIn PDF document text
    • http://amtusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098905085687---bonanunuxopevuzunib.pdfIn PDF document text
    • http://sochistandart.com/ckfinder/userfiles/files/78004513447.pdfIn PDF document text
    • https://tutorsbureau.net/userfiles/file/21463483355.pdfIn PDF document text
    • https://www.popcaffe.it/wp-content/plugins/super-forms/uploads/php/files/c8ae4e2a17395aa3da2c65c2d6c4a306/25620918137.pdfIn PDF document text
    • https://www.pharmaright.ca/wp-content/plugins/super-forms/uploads/php/files/rncco8lbmt5oka2v8ac4nooj54/90534658697.pdfIn PDF document text
    • https://www.dentaltaxpros.com/wp-content/plugins/super-forms/uploads/php/files/fb04a179d6754a98ada7f76132ec5a8e/vetipijexinozesa.pdfIn PDF document text
    • http://www.dnevi-sekretarjev.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16072daff06665---40701268601.pdfIn PDF document text
    • https://aryaayur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc7ca05144f---dalavakedada.pdfIn PDF document text
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/ce8f8aa156223b10095f5b82d029478c/surafowoxexamowiriwiriv.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=state+separation+noticePDF 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_off0000c2fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC2FD 10396 bytes
SHA-256: ed1d3c982d92613902861e162752e1b17763028dfd9c3063d4bd392436952c01
font_01_sfnt_off0000da97.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA97 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f2a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2A9 17316 bytes
SHA-256: 4688eb1782818a7230ab59a902075491c63c29142c7ebbf978afbd5afebbd293