Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5675df3130b4a57…

MALICIOUS

PDF

84.8 KB Created: 2021-09-02 17:26:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: c9a961307117010248a6292bb54a7b50 SHA-1: 7cb2a26acdb55be9ae1182d0ac7b0123d4d53bea SHA-256: c5675df3130b4a5712cc4bce32996a0e46056129f4c4f09136653c99764d83ca
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 are part of a link farm designed to obscure the final destination. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The presence of links to compromised CMS uploads suggests an attempt to leverage existing infrastructure for malicious hosting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://esz.jp/img/editor/files/popakakimavevirovedujudo.pdf In PDF document text
    • http://aisef.org/uploads/userfiles/file/file/52390611497.pdfIn PDF document text
    • https://caribemed.com/userfiles/file/85572685969.pdfIn PDF document text
    • http://mintaialuminum.com/d/files/zifidazodukivegorazu.pdfIn PDF document text
    • http://giustizianuova.it/userfiles/file/9712532486.pdfIn PDF document text
    • http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606d280ce0286---vokivibumavibazamime.pdfIn PDF document text
    • https://guijek.com/userfiles/file/tupijusenimozajev.pdfIn PDF document text
    • http://famcareconnect.org/wp-content/plugins/formcraft/file-upload/server/content/files/16089342eee08b---vowufuvezapuvugesenowod.pdfIn PDF document text
    • http://tunglamgarden.com/images/fck/file/99554617498.pdfIn PDF document text
    • http://edwardnugent.com/userfiles/files/29936210103.pdfIn PDF document text
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a042b7053b7---56519894963.pdfIn PDF document text
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/16072b47a15030---domevixenikomulusasopozi.pdfIn PDF document text
    • http://balade-pierry.fr/userfiles/file/fereminitakasik.pdfIn PDF document text
    • https://machnhaduong.com/images/uploads/files/dutetokamotawoseg.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086eedfd530e---93482609757.pdfIn PDF document text
    • http://belgium-ex.com/images/blog//file/2518371697.pdfIn PDF document text
    • https://optical-axis.com/uploads//files/202108042146422794.pdfIn PDF document text
    • https://www.zaantraining.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608727a5074a5---24942228988.pdfIn PDF document text
    • https://thegmsbihta.in/userfiles/file/maliturexu.pdfIn PDF document text
    • http://graviroz.hu/ckfinder/userfiles/files/pelodamanusidadirulajexux.pdfIn PDF document text
    • http://studiocommercialedelpiano.it/userfiles/files/divapotesetube.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=the+horse+dancer+jojo+moyes+pdfPDF 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_off0000e868.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE868 10856 bytes
SHA-256: c79d8f7d8f853fe46ba481a5f2cdb0399033a60a5fa08d8dc4a67ed9c97b22ef
font_01_sfnt_off00010157.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10157 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011969.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11969 17028 bytes
SHA-256: 46e89990bc44a1d5e094845d43b50ab59a7bd702224c988953ebb7474052f3f2