Malicious PDF — malware analysis report

Static analysis result for SHA-256 7a4fffa713a63e2c…

MALICIOUS

PDF

73.8 KB Created: 2021-09-22 19:02:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: b1e6d089d779312123ef41c93167ebf6 SHA-1: 14c83d23d662d7123484cc349d5057c54137c475 SHA-256: 7a4fffa713a63e2c00dd02237f1a4d4c7016db663071b832aedd874b903e5f48
156 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 compromised websites or disposable hosting, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. The presence of multiple external URIs and link farms points towards an attempt to lure users to external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://ketchas.ru/uplcv?utm_term=bubble+pop+game+unblocked PDF link annotation
    • http://tavaszitura.eu/userfiles/files/7293821602.pdfIn PDF document text
    • https://gallerylingard.com/uploads/file/39700480618.pdfIn PDF document text
    • https://armour-technoz-ca.otzol.net/ckfinder/userfiles/files/29861367031.pdfIn PDF document text
    • http://studiovalentini.eu/userfiles/files/demidawize.pdfIn PDF document text
    • http://lnv-cnc.gr/userfiles/file/16727359329.pdfIn PDF document text
    • https://h1t-url12shio-turbo.com/contents/files/vadifes.pdfIn PDF document text
    • http://strelnicebudejovice.cz/userfiles/file/50646650487.pdfIn PDF document text
    • http://statsale.com/data/upload/ck/files/pukukoruno.pdfIn PDF document text
    • http://www.laterveer-biesenbeek.nl/ckfinder/userfiles/files/93566896699.pdfIn PDF document text
    • http://rydelko.eu/userfiles/file/sojugedef.pdfIn PDF document text
    • http://tanphatinst.com/vietkiendo/upload/file/pafujegejeg.pdfIn PDF document text
    • https://muguet.fr/sites/default/files/file/92656899228.pdfIn PDF document text
    • http://kwiatmetal.pl/userfiles/file/29370255396.pdfIn PDF document text
    • https://inunekocp.jp/mailmagazine/upload/files/14660708447.pdfIn PDF document text
    • http://stacjaregeneracja.pl/userfiles/file/62870331397.pdfIn PDF document text
    • http://www.advancedevents.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161318bfb24837---22029688071.pdfIn PDF document text
    • http://realestatespoznan.com/uploads/4905936594.pdfIn PDF document text
    • https://majubesar.net/contents/files/67195692918.pdfIn PDF document text
    • https://fotokeramika.bg/userfiles/file/68257053512.pdfIn PDF document text
    • https://infotechb2blite.com/bot/ckfinder/uf/files/tefepavob.pdfIn PDF document text
    • https://myhoorayhealth.com/wp-content/plugins/super-forms/uploads/php/files/415c0e941a6aa70eaca1235a8ade693a/46667485518.pdfIn PDF document text
    • http://jingkangchem.com/upload/files/norafowuvakabaxife.pdfIn PDF document text
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16144a46d84545---niduserosomozarusuwixutat.pdfIn PDF document text
    • http://supragyn.cz/userfiles/file/guvozetalojixaronigufag.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_off0000bc23.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC23 16900 bytes
SHA-256: f34ec58d58bf17462d0c79bc495fa4b63ae18d22b1b130bafdf2df44a39fed56
font_01_sfnt_off0000e7af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7AF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ffc6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFC6 10784 bytes
SHA-256: e8f6bd6c78cefec8aa9296f76634f619b66608ebc4bcb87f280ba1c7d09bd1f7