Malicious PDF — malware analysis report

Static analysis result for SHA-256 0d837551b49535fc…

MALICIOUS

PDF

71.2 KB Created: 2021-08-28 11:19:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: cd33d8d457a622bb148f4676b784cc61 SHA-1: 8b0791004cea6de41b7f49e2cde3c022648a103a SHA-256: 0d837551b49535fcf5b25639891eea1bb6c9f3bbe52ae6d662649313f3ec5878
156 Risk Score

Malware Insights

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

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. Heuristics reveal it functions as a link farm, directing users to multiple compromised or suspicious websites, including one hosted on a compromised WordPress upload storage. The presence of numerous PDF link farm URLs suggests a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://partnyor.az/userfiles/file/nigibumapogozopenoxezon.pdf In PDF document text
    • https://homecareangels.ca/files/files/files/44794605429.pdfIn PDF document text
    • http://stensoproject.com/userfiles/files/fazutaxarasena.pdfIn PDF document text
    • https://eminenceconstruction.ca/viking1/uploads/files/88962552741.pdfIn PDF document text
    • http://eastwoodfamily.net/userimages/39521521318.pdfIn PDF document text
    • https://digbijoynath.in/iisc/ckfinder/uploads/userfiles/files/vunamepegirijexerosi.pdfIn PDF document text
    • http://starma.pl/files/file/12240609045.pdfIn PDF document text
    • http://bularz-auto.pl/images/userfiles/file/76828839231.pdfIn PDF document text
    • http://global-poseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fcc1b6d4992---43452187599.pdfIn PDF document text
    • http://nieruchomosci-swidnica.pl/userfiles/file/48566371871.pdfIn PDF document text
    • http://qwerty.pl/_data/file/sidajepizerilemuguki.pdfIn PDF document text
    • http://clubsahdianagalati.ro/upload/editor/file/wugazawifibiraxaza.pdfIn PDF document text
    • https://irish-setter-zucht.info/ckfinder/userfiles/files/16830001342.pdfIn PDF document text
    • http://championshipsportsrings.com/clients/23492/File/69575861563.pdfIn PDF document text
    • http://nyitotthaz.hu/userfiles/files/wozofofezakor.pdfIn PDF document text
    • http://dchs1961.com/clients/871949/File/4522818266.pdfIn PDF document text
    • https://tcufroghouses.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b3e6063f2a---dimum.pdfIn PDF document text
    • http://smart-ventures.ch/upload/Editor_Images/files/81376316250.pdfIn PDF document text
    • http://www.itbaloch.com/wp-content/plugins/formcraft/file-upload/server/content/files/160da313be971b---88036273414.pdfIn PDF document text
    • http://ca1970.com/clients/10044/File/98009519255.pdfIn PDF document text
    • https://global-product.org/CKEdit/upload/files/28392710348.pdfIn PDF document text
    • https://ebooksweb.net/files/file/39402589376.pdfIn PDF document text
    • https://wholisticvibrations.com/wp-content/plugins/super-forms/uploads/php/files/55112a289b3943dc5ed52245c20456a2/85283733871.pdfIn PDF document text
    • https://belgradenightlife.info/wp-content/plugins/super-forms/uploads/php/files/uqmvd3k0jd9rjjsfsflg2rhlam/74688184243.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=how+to+read+better+out+loudPDF 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_off0000b7c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB7C3 10192 bytes
SHA-256: 8f4647b7f18dc608d05faeddd4568aeec7d308f66602c7edc9b72919ce817b53
font_01_sfnt_off0000ceb9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCEB9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e6cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6CB 15944 bytes
SHA-256: 2a69e44b3c450056ec69c32c66e420bb3ff074fbf7811a7ad76e2951cc8ad836