Malicious PDF — malware analysis report

Static analysis result for SHA-256 21ad767c3776fe52…

MALICIOUS

PDF

87.1 KB Created: 2021-06-25 23:44:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 00a0119be5578ce428aaf2994687a6db SHA-1: 9b45651e5b06d75bee5ad2bf7004c8f55b93c24b SHA-256: 21ad767c3776fe5246433aeb7cff8cbcb793981a00b045d33cc08c32ffc93302
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, directing users to multiple external websites, many of which are hosted on compromised WordPress installations or disposable domains. The primary goal appears to be SEO manipulation or directing users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://desertflying.club/wp-content/plugins/formcraft/file-upload/server/content/files/160b4a276875b0---mejomizotubaki.pdf In PDF document text
    • https://www.elektrobetrieb-scholz.de/wp-content/plugins/formcraft/file-upload/server/content/files/16098856dddbc5---dojolezel.pdfIn PDF document text
    • http://www.grupohk.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c0471977d52---sanivibotumowemukipeli.pdfIn PDF document text
    • http://kapsalonvogue.nl/files/file/58518381325.pdfIn PDF document text
    • https://www.psalighting.com/wp-content/plugins/super-forms/uploads/php/files/d266d96f8b0e75ec6f1a24f5402ba5be/69159478205.pdfIn PDF document text
    • https://desertflying.club/wp-content/plugins/formcraft/file-upload/server/content/files/16080f5a27b414---zuverawofojaxat.pdfIn PDF document text
    • https://nscs.org/wp-content/plugins/super-forms/uploads/php/files/4648d17542bdf06275b4e2b2dde7e723/1704595872.pdfIn PDF document text
    • https://www.mclarenpress.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081451894ad1---mawuteju.pdfIn PDF document text
    • http://for-rent-leuven.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609cf3908d03c---28070701852.pdfIn PDF document text
    • https://rescue.bg/wp-content/plugins/formcraft/file-upload/server/content/files/160b31946ac17a---32433953995.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1609faf07a756a---83106860904.pdfIn PDF document text
    • https://www.indee-r.fr/wp-content/plugins/super-forms/uploads/php/files/aa6826357dfc4bf7f7f8215240fdc61b/mivoveregobufezukisik.pdfIn PDF document text
    • https://www.grandiosa.is/wp-content/plugins/super-forms/uploads/php/files/d526b03o2rqta8ct0ck18fdcu1/52373991536.pdfIn PDF document text
    • http://sintellect.ru/Repository/file/84963865321.pdfIn PDF document text
    • https://indacphuc.com/wp-content/plugins/super-forms/uploads/php/files/sd4bfvm0c1jqsr125hkcht7fa5/tenejazenotubipezezotuwog.pdfIn PDF document text
    • http://www.webtony.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16071111ca88a3---tijog.pdfIn PDF document text
    • http://adveotec.com/img/file/tatutuwafiwonasobujuvugaw.pdfIn PDF document text
    • https://bistro-8.com/wp-content/plugins/super-forms/uploads/php/files/dc8e249e23b936291fedc5481dc7a1fc/joviwevagoxivul.pdfIn PDF document text
    • https://universal4shipping.net/userfiles/file/gunonusebazude.pdfIn PDF document text
    • http://nextgenship.net/upload/file/2021060916232289659.pdfIn PDF document text
    • http://freemansphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8cd488682e---7648822065.pdfIn PDF document text
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608087ccbb6d1---woxoza.pdfIn PDF document text
    • http://kayamedbursa.com/userfiles/file/3132971139.pdfIn PDF document text
    • http://www.jhannahs.com/wp-content/plugins/formcraft/file-upload/server/content/files/160830ce69fb0e---98987087891.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=gta+vice+city+online+play+on+androidPDF 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_off0000f2f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2F1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010b08.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B08 10560 bytes
SHA-256: bca3008c34232b39c680caf81b8e9c868e99f447a6776ea082a7b8f2cb2a25bb
font_02_sfnt_off00012346.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12346 16800 bytes
SHA-256: ffbdf30ea8114080186fe868a82bc35ce66045129c3ea0d722998db2a42dd7b6