Malicious PDF — malware analysis report

Static analysis result for SHA-256 7937a4906efbf873…

MALICIOUS

PDF

75.7 KB Created: 2021-06-13 22:50:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-24
MD5: e8dbaba872c47bd74cf5e684630311c4 SHA-1: 24b3b170e6925de33c7eba6fc0df76060a0370d6 SHA-256: 7937a4906efbf8731ea05b82cbedaea5d32d709dfba8ab17ff0f4c31904c7fe9
116 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by an ML classifier. It uses a QR-code lure. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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.
  • QR-code redirect lure medium SE_QR_LURE
    Document instructs the user to scan a QR code with a phone — consistent with QR phishing, but also common in legitimate documents
  • 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://allytemp.ru/uplcv?utm_term=salamander+s5+qr+code PDF link annotation
    • http://cargo3030.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160bfbd1b92d16---ruvelizujemibawifunuduwo.pdfIn PDF document text
    • https://cashofferoregon.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094df395e5c8---16254172763.pdfIn PDF document text
    • http://theydeserveastamp.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607e259445c00---gexatidesevi.pdfIn PDF document text
    • http://www.tobywells.org/media/fckdir/file/53847735119.pdfIn PDF document text
    • http://bogelaipigeon.com/upload/file/viliwesi.pdfIn PDF document text
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b21b2af983---91362498234.pdfIn PDF document text
    • http://hersheyhigh1981.com/clients/37302/File/dusofufetesoromilorugat.pdfIn PDF document text
    • http://boulderdivorcelaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077accfae0c5---duzifufufudakegef.pdfIn PDF document text
    • http://magogaralbamoble.com/galeria/files/modasogop.pdfIn PDF document text
    • https://www.nrlandscapes.co.uk/wp-content/plugins/super-forms/uploads/php/files/44f8d5540aa1d09de0b542a8debbc8dd/52531870062.pdfIn PDF document text
    • https://ehblending.com/wp-content/plugins/super-forms/uploads/php/files/0196d18b41ae2b2fc6636fa53789af7f/tinar.pdfIn PDF document text
    • http://aep-tc.com/cache/fck_files/file/kuwuzabuzuwutejukevi.pdfIn PDF document text
    • https://thesmithgrouphouston.com/wp-content/plugins/super-forms/uploads/php/files/f9e8bfa2d314cabd706f60e7aef82b95/18395185343.pdfIn PDF document text
    • https://haps.company/wp-content/plugins/super-forms/uploads/php/files/05tb97ekbct4o46iuc0go5d9f0/73861193629.pdfIn PDF document text
    • https://www.elektrobetrieb-scholz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160710128c88ce---50739745156.pdfIn PDF document text
    • https://www.diktu.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609cf880e7d63---9476223533.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000eae9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAE9 5436 bytes
SHA-256: 6199bed69a567a3c440cc5c62b3d769e0f8b7b11c901572bc784d0a25faeeca0
font_01_sfnt_off0000fd4f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD4F 10944 bytes
SHA-256: 059fe912cd232591b96a9b75db19bdc875d1ff8511369661e9b3656c7d9b1dd2