Malicious PDF — malware analysis report

Static analysis result for SHA-256 a91b654f7cc63be5…

MALICIOUS

PDF

72.3 KB Created: 2021-09-03 02:07:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 4cee016beae60a4424cc6a10f0a27c46 SHA-1: af26a154ff28f38d1e48f48805a795e59fe8a9ab SHA-256: a91b654f7cc63be57fd752e249aa1ec0b74b4538096fc5ede8e48deaf5a48d54
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to download other PDFs from compromised WordPress sites and disposable hosting domains. The presence of numerous links to potentially malicious PDF files suggests a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://mega.kz/media/upload/files/subapibup.pdf In PDF document text
    • http://bronia.org/userfiles/file/62228948073.pdfIn PDF document text
    • http://www.alwaysflorida.com/wp-content/plugins/formcraft/file-upload/server/content/files/160788b5c1b9ca---rawaropogelasixixis.pdfIn PDF document text
    • https://www.temtechnologies.fr/ckfinder/userfiles/files/ruwadavita.pdfIn PDF document text
    • https://ooobelkom.ru/ckfinder/userfiles/files/55259138617.pdfIn PDF document text
    • https://www.glasswindowequipment.com/wp-content/plugins/super-forms/uploads/php/files/715332758fe98702fea21f7750b0cb1a/panotufujesawozali.pdfIn PDF document text
    • https://law.myvzl.com/wp-content/plugins/super-forms/uploads/php/files/rh3d8626p8ss1bu2d51i90gck9/68408128634.pdfIn PDF document text
    • http://www.unidacardoso.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160bd6622ccc8d---dekusumovemuvosididujagax.pdfIn PDF document text
    • http://bakkervoorwinde.nl/app/webroot/files/ckeditor_files/files/90684468297.pdfIn PDF document text
    • http://80tner.friend-match.com/upload/files/82340341861.pdfIn PDF document text
    • http://angeladaniel.eu/uploads/files/mowixerakajokuw.pdfIn PDF document text
    • https://pfhotel.gr/ckfinder/userfiles/files/politiputojula.pdfIn PDF document text
    • https://numen-wow.com/userfiles/cloud//files/91160826497.pdfIn PDF document text
    • http://ambulatorioveterinarioilprato.eu/userfiles/files/tetaposakixegelu.pdfIn PDF document text
    • http://danchrisjewelry.com/userfiles/file/32082504537.pdfIn PDF document text
    • https://estidevelopers.com/wp-content/plugins/super-forms/uploads/php/files/80846238cf2c44c3da21ffb54b7b2e6b/zowegodagovogunugon.pdfIn PDF document text
    • http://popnmusic.fr/userfiles/file/77776138947.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608d17ecaa408---suvalopukafugixuk.pdfIn PDF document text
    • http://edwardnugent.com/userfiles/files/67193847516.pdfIn PDF document text
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16121834c08300---37260990541.pdfIn PDF document text
    • http://xn--9n2bn9mz3aba29g44r4o0a.kr/fckeditor/userfiles/image/riritutid.pdfIn PDF document text
    • https://travels-ukraine.com/wp-content/plugins/formcraft/file-upload/server/content/files/160897d508af57---welanazefugesu.pdfIn PDF document text
    • http://ubestsports.com/imager/files/20210814222446.pdfIn PDF document text
    • https://marjoyunlar.com/calisma2/files/uploads/paxotobuluxuxi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=hs+code+list+2019+pdfPDF 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_off0000b8f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB8F3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d105.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD105 16428 bytes
SHA-256: ac97a4994c9686e26dcd3ca336200d081fa548e2493ca7df30555be2106e2549
font_02_sfnt_off0000fb5e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB5E 10700 bytes
SHA-256: 736a0c9e0a7de1f1fb85484d6ad1143de1b5dd108f9316efb38b1f9f15763219