Malicious PDF — malware analysis report

Static analysis result for SHA-256 288ba39906763724…

MALICIOUS

PDF

83.5 KB Created: 2021-09-13 02:12:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: aea162085168d5ede1e35b56b946f17e SHA-1: 8f238380443b4ab7a3a4281bef4037e453960b6f SHA-256: 288ba3990676372423a6785ce5dc97a1e349b321a60acd1af2e68d01900b4550
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm with numerous distinct hosts, suggesting an attempt to obscure the ultimate destination of redirects. While no scripts were explicitly extracted, the PDF structure and the presence of many external URIs point towards a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://naasschoolofmotoring.ie/fckeditor/userfiles/file/55669889043.pdf In PDF document text
    • https://doctmcooper.com/userfiles/files/34352425807.pdfIn PDF document text
    • http://www.southforconstruction.com/frontend/web/ckfinder/userfiles/files/ruvupirelugozosewovepasej.pdfIn PDF document text
    • https://pluviaterra.mx/wp-content/plugins/super-forms/uploads/php/files/3560551261265b851ef5089224f7c1de/42772060308.pdfIn PDF document text
    • http://hawaiianhunareiki.it/file/63879772768.pdfIn PDF document text
    • http://gd-weimi.com/upfolder/e/files/20210908100444.pdfIn PDF document text
    • http://noospc.ru/SITE/files/editor/file/fejuzepixi.pdfIn PDF document text
    • http://school19-zav.ru/userfiles/file/1431627342.pdfIn PDF document text
    • http://ahzgbh.news-read.com/upload/files/zulimugusodowulepumin.pdfIn PDF document text
    • http://zenobiacultura.it/userfiles/file///44074108191.pdfIn PDF document text
    • https://dpengineerindia.com/admin/userfiles/file/95330365199.pdfIn PDF document text
    • http://khonggianmang.com/upload/files/7435880686.pdfIn PDF document text
    • https://ermolino.mebel18.com/uploads/files/rubofinofadajod.pdfIn PDF document text
    • http://sxhk365.com/uploads/file///10474381504.pdfIn PDF document text
    • https://masini-de-ambalat.ro/images/userfiles/82149918812.pdfIn PDF document text
    • http://feynburg-uhren.de/uploads/volowemu.pdfIn PDF document text
    • http://pferdefreunde-brueckenhof.de/sites/default/files/userfiles/file/13195359441.pdfIn PDF document text
    • http://geoman.cz/data/file/28721086966.pdfIn PDF document text
    • http://boilerservis.ru/uploads/files/8533778421.pdfIn PDF document text
    • http://change4best.ru/upload/file/wifenovagunumumetaro.pdfIn PDF document text
    • http://trevelci.ru/ckfinder/userfiles/files/4847242808.pdfIn PDF document text
    • http://myapartment.de/web/editor/files/gezedulagokazorajupowiwad.pdfIn PDF document text
    • http://umffz21.ru/admin/ckfinder/userfiles/files/35593723971.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=set+trade+androidPDF 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_off0000e205.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE205 10100 bytes
SHA-256: 558ff08525bcea86f55f9c70330014b524aee8c5c9e41e923c3add12609619b2
font_01_sfnt_off0000f8a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8A5 18556 bytes
SHA-256: 73d4cd581cb3538c06e7ae6e27e704e6faf21c7b1d4a4abb1c292b49a12cf44f
font_02_sfnt_off000128a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128A1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1