Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a5a0d1800eb627f…

MALICIOUS

PDF

77.1 KB Created: 2021-09-07 23:33:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 9c6686d7ad95dd62c542f1923d58e2d2 SHA-1: 57fc623724135182f73a4651b78fe91dbd8bcfb5 SHA-256: 4a5a0d1800eb627f568c1255f389691021b4aa79ce58a3c19212f0cb1546b548
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, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many pointing to compromised CMS upload storage or disposable hosting, suggesting it functions as a link farm. The primary purpose appears to be directing users to external, potentially malicious, sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://www.bbmnetlicitacoes.com.br/cms/ckfinder/upload/files/gutobi.pdf In PDF document text
    • https://www.harnoordesigns.com/wp-content/plugins/super-forms/uploads/php/files/19n6ebjoop88n6q0pnrr1oi873/51325902020.pdfIn PDF document text
    • http://litho-and-co.fr/ckeditor/upload/files/22757842668.pdfIn PDF document text
    • http://carsongrad75.com/clients/3/35/35717660c32d3dd9b0ffde8f33a19d23/File/lozez.pdfIn PDF document text
    • http://baovephuongtroi.com/vietkiendo/upload/file/93506823134.pdfIn PDF document text
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/160983c3cd5180---97871023668.pdfIn PDF document text
    • http://logistra.fr/ressource/site-image/files/rilotinisaxe.pdfIn PDF document text
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16094e762dafb3---13696948606.pdfIn PDF document text
    • http://fslawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/fariromatanoji.pdfIn PDF document text
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/q6fv78n20qrl8k80i1m1ck3rs6/zarefunupatu.pdfIn PDF document text
    • http://33podarka.ru/pictures/files/zigabavobirixazi.pdfIn PDF document text
    • https://www.spoton.pet/wp-content/plugins/super-forms/uploads/php/files/pbrd8669ofjeoqpom37a2bkv49/memegodu.pdfIn PDF document text
    • https://earthideasawnings.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607eeacac42ca---22582067880.pdfIn PDF document text
    • https://www.analfissur.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075860e6b823---78834791767.pdfIn PDF document text
    • http://wakingbeauty.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607181b1c8b97---nolajefevimura.pdfIn PDF document text
    • https://heks-tech.com/app/webroot/userfiles/files/14032597452.pdfIn PDF document text
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b743690d94a---woveniwanirakosox.pdfIn PDF document text
    • http://manisafar.com/basefile/marcosafarir/files/divegagutorab.pdfIn PDF document text
    • http://masseydogs.com/clients/f/fc/fc2e217ffa4851e49ca3cd921a15cf41/File/52236682639.pdfIn PDF document text
    • https://www.marvistasales.com/wp-content/plugins/super-forms/uploads/php/files/b0080911df171187aa8fdaf33370f89d/xobuxilibepanamejepi.pdfIn PDF document text
    • http://ttccid.com/userfiles/file/wezebabal.pdfIn PDF document text
    • http://beta-rc.com/upload/files/kipaveto.pdfIn PDF document text
    • https://canvasations.com/wp-content/plugins/super-forms/uploads/php/files/3597ba4182a0659088b193c196a90fdd/jatabitanebofurumuz.pdfIn PDF document text
    • http://mirrorgallery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ab84282208---24147957672.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=convert+pdf+en+excel+online+gratisPDF 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_off0000c672.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC672 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000de89.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE89 10992 bytes
SHA-256: 36b06568967666e052f47c4b34fba655b01cd862c3f225465d15c5b8415e8dfe
font_02_sfnt_off0000f80d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF80D 18088 bytes
SHA-256: 6eace54774693e7a7ef5e56541867452dfc4f7203be43057e17c42bd0cc7dd33