Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4ca0b4d740c73e2…

MALICIOUS

PDF

69.8 KB Created: 2021-09-26 03:53:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: ed0cbcf71dcd4c4013cb90184ff1a807 SHA-1: 1ba6daaf94a6f72f456b6dc479117d063325d7fd SHA-256: c4ca0b4d740c73e293ef4e38dfad975a563032396f88f301033594037fd84349
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 CMS upload storage or disposable hosting, indicative of a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are consistent with a malicious PDF dropper.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 http://www.tecnobor.com/ckfinder/userfiles/files/sitajijenogosodusefo.pdf In PDF document text
    • http://lesen-und-schenken.de/userfiles/files/35609581278.pdfIn PDF document text
    • http://cukrarnakolbaba.eu/obrazky/files/63528054930.pdfIn PDF document text
    • http://ouhkpthaa.org/userfiles/buden.pdfIn PDF document text
    • http://ongxoanhdpe.vn/upload/files/fivumomuzefaximawuruzuned.pdfIn PDF document text
    • http://dierenwinkelindex.nl/images/uploads/58521711785.pdfIn PDF document text
    • http://fabiocaronearchitetto.com/userfiles/files/pasapopotoxixez.pdfIn PDF document text
    • http://classicalgardenornaments.com/uplds/file/19213914873.pdfIn PDF document text
    • https://ra7a7p-h3ba7.com/contents/files/nigedodak.pdfIn PDF document text
    • https://broadcasthub.com/ci/userfiles/files/wazuzej.pdfIn PDF document text
    • https://www.popcaffe.it/wp-content/plugins/super-forms/uploads/php/files/342006af3d2610e24fdf136d61c89823/dopimizin.pdfIn PDF document text
    • http://flex-link.cn/uploadfiles/files/3705105610.pdfIn PDF document text
    • https://osikovo.eu/webroot/img/content/files/tidelexonafetivizaneniz.pdfIn PDF document text
    • https://jpjplumbingandheating.com/FCKeditor/file/71253807882.pdfIn PDF document text
    • http://spartapr.com/images/upload/file/komorax.pdfIn PDF document text
    • http://maraulsan.com/ckfinder/userfiles/files/49669396240.pdfIn PDF document text
    • https://www.medipratik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b1e2487da0---piwilamuvewudaradojunova.pdfIn PDF document text
    • https://autosofortkauf.ch/wp-content/plugins/super-forms/uploads/php/files/u8sqtn2lksmrvgpnnhkn7l5isb/45481392895.pdfIn PDF document text
    • http://apsara.ru/userfiles/file/20761694100.pdfIn PDF document text
    • http://www.zywawiara.pl/pliki/revurodexovakisev.pdfIn PDF document text
    • http://radtel-sport.pl/userfiles/file/lelazazamebuxul.pdfIn PDF document text
    • https://relaxbotanika.cz/ckfinder/userfiles/files/796448440.pdfIn PDF document text
    • http://www.anapharmata.hu/ckfinder/core/connector/php/files/24848000117.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=instagram+2018+version+apk+downloadPDF 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_off0000afa0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAFA0 15420 bytes
SHA-256: 89bcb2fe87e5e583d46badf15f408c25f31dfbd31235f7c137f1ec5806348ce2
font_01_sfnt_off0000d712.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD712 11432 bytes
SHA-256: 25262523f99e733d088dad98f5de920d050939a23ad6cfc130df30e8f9d1ebd8
font_02_sfnt_off0000f1fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1FD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1