Malicious PDF — malware analysis report

Static analysis result for SHA-256 f23be78f1f962676…

MALICIOUS

PDF

86.6 KB Created: 2021-07-07 22:07:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 73e5fa73bcf76e1671d3328105942041 SHA-1: 7824987a521beb692ed47aab142616a34d974973 SHA-256: f23be78f1f962676b23dfc3e9c4d39f0c61024295a2775f266c6e5ba595260df
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains numerous embedded URLs pointing to various websites, many of which appear to be compromised WordPress installations used for hosting PDF files. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution through these links. No scripts were extracted, but the structure suggests a link farm designed to obscure the final destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://catamma.ru/uplcv?utm_term=delicious+roasted+sweet+potatoes PDF link annotation
    • http://aihyang.com/userfiles/file/nutemukerizabiw.pdfIn PDF document text
    • http://cargo3030.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9b78dbb80---44800974174.pdfIn PDF document text
    • http://raunlarose.us/wp-content/plugins/formcraft/file-upload/server/content/files/16093cc003a5c2---kozimixamofoja.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/689e30c7d1c0fea74a211d0d01d1cdef/sizev.pdfIn PDF document text
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160d319142240a---10323393638.pdfIn PDF document text
    • https://micast.de/wp-content/plugins/super-forms/uploads/php/files/lo5pho40mfdshv35meslvu1p9j/xatit.pdfIn PDF document text
    • http://omonetach.pl/foto/ilustracje/file/sesonozajomavogala.pdfIn PDF document text
    • http://pensacolahigh1964.com/clients/1/1d/1d652d7f5bd5fd2f3712913460b20393/File/bosisanibuxo.pdfIn PDF document text
    • https://naseeha.org/wp-content/plugins/super-forms/uploads/php/files/8177fe63591660a8cc85a03b10c830bb/vinolixivefidavajujanufi.pdfIn PDF document text
    • https://homeaestheticsllc.com/wp-content/plugins/super-forms/uploads/php/files/f36b8a9d569b64bd76ea5a2b96d49124/91928492671.pdfIn PDF document text
    • https://www.dishdivvy.com/wp-content/plugins/super-forms/uploads/php/files/191c7e89ba6c9e9872efaec475bb448d/zesopine.pdfIn PDF document text
    • http://feuerwehrobrigheim.de/upload/files/95900088532.pdfIn PDF document text
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/160b21465d7ada---razesezarawetoperu.pdfIn PDF document text
    • http://web68s.com/upload/files/diwujizut.pdfIn PDF document text
    • https://masini-de-ambalat.ro/images/userfiles/xivalowifujutuxupeguw.pdfIn PDF document text
    • http://jeremypourstarlight.com/clients/5/53/539822683240d2210db56c0084569a8b/File/67759603293.pdfIn PDF document text
    • http://akcjonariusz.com/UserFiles/file/21522669833.pdfIn PDF document text
    • http://dom-2000.ru/ckfinder/userfiles/files/62891690298.pdfIn PDF document text
    • http://www.airportlimofortlauderdale.net/wp-content/plugins/formcraft/file-upload/server/content/files/16090f6d5b9e7a---gumapefozek.pdfIn PDF document text
    • https://www.auditek.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160a703684d182---84957626088.pdfIn PDF document text
    • http://sanarina.de/ckfinder/userfiles/files/1615374030.pdfIn PDF document text
    • http://ahdongjiu.com/upload_fck/file/2021-5-1/20210501230227412620.pdfIn PDF document text
    • http://hebammenglueck.de/ckfinder/userfiles/files/25226314237.pdfIn PDF document text
    • https://argumentua.com/i/file/kipibevirotowifasodukixar.pdfIn PDF document text
    • http://alpanelektrik.com/depo/sayfaresim/file/29643725652.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_off0000efed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFED 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010804.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10804 10592 bytes
SHA-256: e9cc77985fa3cb306ebef6518662952bdaf0d36959bdf1e65e47f483e7977de9
font_02_sfnt_off0001206b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1206B 17068 bytes
SHA-256: fd486be5089f3bd976ce94b02514de6259227677247b7fb19e64ad49bae80d59