Malicious PDF — malware analysis report

Static analysis result for SHA-256 376dd858336590c4…

MALICIOUS

PDF

78.7 KB Created: 2021-09-13 14:07:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 2d16684ffbec868d82b8282c2267a75a SHA-1: c87de86fc1808aef6888633b7c8bd3bc0d71ae33 SHA-256: 376dd858336590c4c07e3f17c969a762e912cefa0c20ce155676d4a646ef8d00
156 Risk Score

Malware Insights

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

This PDF was identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It functions as a link farm, containing numerous URLs pointing to potentially compromised or disposable hosting domains. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using such domains for SEO manipulation or to host malicious content, and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' suggests exploitation of content management systems.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://thy-environment.com/userfiles/files/waboxetifepupapebov.pdf In PDF document text
    • https://asiarsolutions.com/userfiles/file/72342731737.pdfIn PDF document text
    • http://keystoparadise.com/userfiles/files/99022363460.pdfIn PDF document text
    • http://bradzo-ep.com/uploads/files/33551093435.pdfIn PDF document text
    • http://laboratoriologos.it/userfiles/files/sejazepilo.pdfIn PDF document text
    • https://mkart.it/uploads/file/ridujoserofupiwilefi.pdfIn PDF document text
    • http://mastera-mix.ru/ckfinder/userfiles/files/wojuguz.pdfIn PDF document text
    • https://grootformaatspandoeken.nl/userfiles/file/16007534041.pdfIn PDF document text
    • https://best-label.com/upload/files/81558201397.pdfIn PDF document text
    • http://guoyangmoju.com/userfiles/files/gilepugilafenasim.pdfIn PDF document text
    • http://cargo3030.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16132000b420ca---70753841412.pdfIn PDF document text
    • https://himalayanthailand.com/image/upload/File/67163993266.pdfIn PDF document text
    • https://www.diktu.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133bca2b9b04---lapip.pdfIn PDF document text
    • https://daynexweb.com/upload/ckfinder/files/nofovubabozizovixusatar.pdfIn PDF document text
    • http://getsolarny.com/userfiles/file/56242749617.pdfIn PDF document text
    • https://permargi.com/files/galeria/files/43067842965.pdfIn PDF document text
    • http://lunaleo.pl/userfiles/file/vafufewukunitekozebike.pdfIn PDF document text
    • https://grafconsulting.pl/Upload/file/fepif.pdfIn PDF document text
    • http://global-gypsum.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ad4b1938fc---xuvasepiremaginob.pdfIn PDF document text
    • http://lex.tj/img/file/82067943601.pdfIn PDF document text
    • http://jikaramen.com/uploads/files/xubinedepatutexebozuwa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=protocols+used+in+each+layer+of+osi+modelPDF 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_off0000d1e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1E8 16412 bytes
SHA-256: ccdd77533519cd327e150de51f29e1b1b0b08a5d6fc0c2f52a58829c62f04b90
font_01_sfnt_off0000fbec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBEC 10956 bytes
SHA-256: ef54872c7c3869510495d10def17ede3ceb05d3c6dedc6ebb0a1f80cd6ae259e
font_02_sfnt_off0001152a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1152A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1