Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5488d8dd99782d3…

MALICIOUS

PDF

70.9 KB Created: 2021-09-21 01:30:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 20c6de5a3384b62bf5cf5d03af9bf8cb SHA-1: ad68bde5ff2f8f7e9f32235c16587ee8eb8960ef SHA-256: b5488d8dd99782d3df991f755bf3e7a72e6aa3ca6da22dfc5140ec62c3cdd3f6
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs that point to various websites, many of which appear to be compromised or disposable hosting. The ML classifier strongly indicated maliciousness, and the heuristic firings suggest this PDF is part of a link farm designed to redirect users. The primary goal appears to be directing users to external, potentially malicious, sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 5

  • 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://medvor.ru/uplcv?utm_term=each+planet+in+order PDF link annotation
    • https://myhoorayhealth.com/wp-content/plugins/super-forms/uploads/php/files/7c8c80b9021c9c0b7f85afc6cc052c2b/6394350978.pdfIn PDF document text
    • http://bpabv.nl/uploadfiles/file/53620321768.pdfIn PDF document text
    • https://hatinhjobs.com/upload/files/wijavazisu.pdfIn PDF document text
    • http://trip-sale.ru/userfiles/file/jilawasoralawite.pdfIn PDF document text
    • https://centaur.vri.cz/docs/files/20670813919.pdfIn PDF document text
    • http://maurovalleferroarchitetto.eu/userfiles/files/43472549235.pdfIn PDF document text
    • https://www.sistemkabin.com/ckfinder/userfiles/files/polesev.pdfIn PDF document text
    • https://www.americanapi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c4255c8f78---66774719648.pdfIn PDF document text
    • https://it-remarketing.pl/app/webroot/media/files/vaganemimejufori.pdfIn PDF document text
    • https://bwhe.in/ckfinder/userfiles/files/22114802189.pdfIn PDF document text
    • http://laibros.com/ckeditor/userfiles/files/sonaziximekini.pdfIn PDF document text
    • http://janjoling.com/public/ckfinder/userfiles/files/vagina.pdfIn PDF document text
    • http://www.aceitunasdelguadalhorce.es/ckfinder/userfiles/files/60788225532.pdfIn PDF document text
    • http://designklasse.de/ckfinder/userfiles/files/26842714232.pdfIn PDF document text
    • http://www.ppk-kp3k.kkp.go.id/ver2/extra/ckfinder/core/connector/php/media/ckfinder/files/ripokamopijunuruj.pdfIn PDF document text
    • http://lamorenj.com/userfiles/files/17432300057.pdfIn PDF document text
    • http://www.moyekolodin.com/files/godulaxudi.pdfIn PDF document text
    • http://bilagroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/161343eaeab782---navatexorigojosevod.pdfIn PDF document text
    • https://taichielite.com/louis/taichi/ckfinder/userfiles/files/pusuw.pdfIn PDF document text
    • http://kidzcastleschool.com/singhania/downloads/file/fuxomuxevivinidefagiro.pdfIn PDF document text
    • http://rund-sro.cz/UserFiles/File/bujipejotoxumag.pdfIn PDF document text
    • http://shinhwajudan.com/userData/board/file/xufixubavajagupas.pdfIn PDF document text
    • http://xn--j1aai7d.xn--p1ai/userfiles/file/nanotofevodidowemoxewevik.pdfIn 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://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_off0000b662.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB662 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ce79.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE79 10424 bytes
SHA-256: 1cb9513dbe94f1b7a67eaa907241097cb7cec35bba18619de39c1234cafeee7e
font_02_sfnt_off0000e5f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5F7 15876 bytes
SHA-256: 2001c00e5f2acfdb17b7d1099a6bd644e7cfecf5af8bcb2fdab0d8bcb38e31d8