Malicious PDF — malware analysis report

Static analysis result for SHA-256 a0c768f544d1459d…

MALICIOUS

PDF

71.8 KB Created: 2021-10-10 08:23:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: b155bd7cbf514aeb2badda11a61f6776 SHA-1: f6ed4a93561277f12649a2900d1649f758cd5255 SHA-256: a0c768f544d1459dd430fb1eda7c02b1da5484935702ac7c9f3ae8554900815d
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised WordPress upload directories and other disposable hosting sites, indicative of a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. No scripts were extracted, but the structure and URL patterns are consistent with a phishing lure.

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 https://crysiq.ru/uplcv?utm_term=fraught+with+difficulty PDF link annotation
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614207cbb2ec9---20597184212.pdfIn PDF document text
    • https://esofagopisa.it/userfiles/file/dogebeboki.pdfIn PDF document text
    • https://weborder.cloud/userfiles/file///76484490621.pdfIn PDF document text
    • http://scamps.biz/userfiles/file/97239751025.pdfIn PDF document text
    • https://zoorichi.com/temp/fckeditor/file/95641993234.pdfIn PDF document text
    • https://somogyplusz.hu/files/54795216879.pdfIn PDF document text
    • https://xn--22ck6bdp5cach0mc23a.com/ckfinder/userfiles/files/nisikagevusuv.pdfIn PDF document text
    • https://questfran.com/broker-site/files/files/90474587416.pdfIn PDF document text
    • http://drcleancenter.com/uploads/files/202110021953578561.pdfIn PDF document text
    • http://acmemask.com/upfiles/editor/files/daxonodurixagozud.pdfIn PDF document text
    • http://parmalab.it/userfiles/files/85086303817.pdfIn PDF document text
    • http://fizjoactiv.eu/Upload/file/sopuzolul.pdfIn PDF document text
    • http://villaturri.it/wp-content/plugins/formcraft/file-upload/server/content/files/1612f1ead4d0fa---gusogofaz.pdfIn PDF document text
    • https://sdhouse.info/ckfinder/userfiles/files/sateniwagagesemigiredu.pdfIn PDF document text
    • https://uleiuri.ro/userfiles/file/55044208576.pdfIn PDF document text
    • https://vinamex.info/uploads/news_file/nijax.pdfIn PDF document text
    • http://kooijobs.in/ckfinder/userfiles/files/3617272666.pdfIn PDF document text
    • http://geerhannutpourreussir.be/docs/upload/files/guxomugidaran.pdfIn PDF document text
    • https://suksesunited.com/contents/files/vibubomepo.pdfIn PDF document text
    • http://bigdoughpizza.com/uploads/files/bukabuxijukut.pdfIn PDF document text
    • http://www.jimenez-casquet.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b97570aa81---xuzuruselovaf.pdfIn PDF document text
    • https://phongkhamtamthan.net/uploadeditor/files/72429398362.pdfIn PDF document text
    • http://bongoes62.dk/userfiles/file/7643425252.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_off0000b597.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB597 17100 bytes
SHA-256: 08109dd02c516a2617e9e5e0c39e5610b943dba596f474dfd693b4ee0fc6edbc
font_01_sfnt_off0000e20a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE20A 10508 bytes
SHA-256: 583771735005101777d04cdbb20f2063de21b7b9a0a5373c0f0bbc50b2e34a2c
font_02_sfnt_off0000f9dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9DC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1