Malicious PDF — malware analysis report

Static analysis result for SHA-256 1b79c5e978ca492f…

MALICIOUS

PDF

89.2 KB Created: 2021-09-07 12:09:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: b50bf418e40d015e136b1540e9593064 SHA-1: 10f62c55ecd34a9f2fd8c1ce538ee1247d62e836 SHA-256: 1b79c5e978ca492f95e0b8e0ecfb927d592af413f47ebff9cb98e80e59769d13
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to domains flagged as compromised or disposable. The ML classifier strongly indicated maliciousness, and the heuristic firings suggest this PDF is part of a link farm designed to direct users to external sites. The presence of these links indicates an attempt to lure users to potentially malicious destinations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

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 http://coffee33.ru/archive/file/jakaxesadivukedemavuvo.pdf In PDF document text
    • http://www.forteks.com.br/admin/ckeditor/ckfinder/userfiles/Images/xutos.pdfIn PDF document text
    • http://dallaslandscapedesign.com/media/files/73951287998.pdfIn PDF document text
    • http://pune-india.info/userfiles/file/rigewapokegolizuzoram.pdfIn PDF document text
    • https://travelselection.us/wp-content/plugins/formcraft/file-upload/server/content/files/160740aa4d461f---tutuvaromuxumoletepesi.pdfIn PDF document text
    • http://picassogift.com/Uploadfiles/files/81807158628.pdfIn PDF document text
    • http://hasyo.net/files/file/5884701463.pdfIn PDF document text
    • http://thanhlapcongtykiengiang.com/upload/ck/files/61712107058.pdfIn PDF document text
    • https://www.infratechgroep.nl/wp-content/plugins/super-forms/uploads/php/files/0a4bacabc5a814497280bb27a239252b/31014726549.pdfIn PDF document text
    • http://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d2682a0b6c---lonunuxusubasa.pdfIn PDF document text
    • http://fapannimario.it/userfiles/files/64269008476.pdfIn PDF document text
    • https://refour.eu/wp-content/plugins/super-forms/uploads/php/files/b8a98f80c915b99458c298d4e42bd3cc/1526003747.pdfIn PDF document text
    • http://diagonal.org.ar/wp-content/plugins/formcraft/file-upload/server/content/files/160881c2d86d06---52423710706.pdfIn PDF document text
    • http://trenermichal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607d91ade0659---lixaselaju.pdfIn PDF document text
    • http://www.empresshasnoclothes.com/siteuploads/editorimg/file/54121985440.pdfIn PDF document text
    • https://alatheir.com/atheirwsfiles/file/lubepupidabasetobidabumev.pdfIn PDF document text
    • https://tcufroghouses.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608601c73fde5---25425896780.pdfIn PDF document text
    • https://actor-conseil.com/files/file/jojorafobobipenedewo.pdfIn PDF document text
    • https://10kshot.com/customerinterview/ckfinder/userfiles/files/laruzid.pdfIn PDF document text
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606c94771d345---busiziwiti.pdfIn PDF document text
    • http://antik-cafe-bergen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ecab0ed593f---36361453576.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=patrones+de+alta+costura+pdfPDF 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_off0000f0d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0D5 21528 bytes
SHA-256: 932eee211c7274efc118add093264c7a21f9df76dab0e66b81df4894f44135ff
font_01_sfnt_off00012750.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12750 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013f67.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13F67 10624 bytes
SHA-256: 729c510e5faf238c4819e715c1085097a192535215539c929d05ebc84ee4f30f