Malicious PDF — malware analysis report

Static analysis result for SHA-256 85312a35cbe6ead9…

MALICIOUS

PDF

80.7 KB Created: 2021-09-15 19:05:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 9d01988276233422124f251cacc061b8 SHA-1: f06a23a4cde16c8c2efd06d7caa9cf40dfd6d4b3 SHA-256: 85312a35cbe6ead975aee3fba287fecd00ecf879048e48c9258682a1848d2584
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm with numerous URLs, several of which point to compromised WordPress uploads, indicating a potential phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or delivering a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://nomylo.ru/uplcv?utm_term=what+is+background+check+in+android PDF link annotation
    • http://kurier48.pl/files/userfiles/file/kewidolev.pdfIn PDF document text
    • https://sskundal.com/userfiles/file/95167085832.pdfIn PDF document text
    • http://luxlustry.ru/img/upload/47038246397.pdfIn PDF document text
    • http://www.sparkprototypes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c6ad2128fe---27481377477.pdfIn PDF document text
    • https://flylights.pl/wp-content/plugins/super-forms/uploads/php/files/6jq7sb805kn723dbhqi85fudfl/xabofebarigokomavezisat.pdfIn PDF document text
    • https://pracowniatechart.pl/fckpliki/file/wapotenexerer.pdfIn PDF document text
    • https://proartgaleria.hu/files/files/81242506274.pdfIn PDF document text
    • http://swancentive.com/cote_dor_import/admin/ckfinder/userfiles/files/30574044861.pdfIn PDF document text
    • http://novafish.it/userfiles/files/28456903634.pdfIn PDF document text
    • http://aeskulap24h.de/wp-content/plugins/formcraft/file-upload/server/content/files/1612febf890e92---54524370327.pdfIn PDF document text
    • http://zjqzzx.com/uploadfile/file/2021090412183473499.pdfIn PDF document text
    • https://www.crossfitparamaribo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138e6f349258---julazozexopesulegafitufug.pdfIn PDF document text
    • http://www.mbk-montage.nl/ckfinder/userfiles/files/36874807507.pdfIn PDF document text
    • http://www.rosabrockenhaus.ch/ckfinder/userfiles/files/keloxaxurujasili.pdfIn PDF document text
    • https://bestcaps99.com/ckfinder/userfiles/files/xoxirat.pdfIn PDF document text
    • https://stmpallet.com/ckfinder/userfiles/files/ratow.pdfIn PDF document text
    • http://www.ctnphrae.com/ckfinder/userfiles/files/poxuwasejixirivavaxatana.pdfIn PDF document text
    • http://aucoindeshalles.com/menu/file/68799403363.pdfIn PDF document text
    • http://bizwd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613156f79aab9---rabinivadezewatufaximuri.pdfIn PDF document text
    • http://officegate.biz/admin/fck_upload/file/fajajenanofet.pdfIn PDF document text
    • http://austral-immo.com/userfiles/files/begomagowozulabupawaxuvur.pdfIn PDF document text
    • https://liantoong.com/archive/upload/files/tusalupekivudewowufokan.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_off0000d445.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD445 18428 bytes
SHA-256: bf5e2db086e115ae89f25818319e25c16a72467488bfd9db3c67d8fee11face3
font_01_sfnt_off00010412.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10412 10928 bytes
SHA-256: e327279720c2528952645c590f5812b70e2e584f81701f67a704e97e7b469d93
font_02_sfnt_off00011d36.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D36 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1