Malicious PDF — malware analysis report

Static analysis result for SHA-256 bf5c7a0161b4de68…

MALICIOUS

PDF

88.3 KB Created: 2021-09-02 22:20:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 62daa919321362ad6eba94c1c72be63f SHA-1: 1fa46f6de3efdaa00b881ac65996f01131c0c70b SHA-256: bf5c7a0161b4de68cda49fda1b9343289352875e6ec8b41349ffd0a21daa857e
156 Risk Score

Malware Insights

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

The sample was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, directing users to multiple compromised websites hosted on potentially disposable infrastructure. The presence of numerous PDF links, many pointing to WordPress upload directories, suggests a tactic to obscure the true destination and evade detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://bartonsteel.com/tony/barton/ckfinder/userfiles/files/zuxosutox.pdf In PDF document text
    • http://www.hotel-margherita.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606e4403a6f34---66893875300.pdfIn PDF document text
    • https://www.servicioscalibrados.com/wp-content/plugins/super-forms/uploads/php/files/2373102d5699fa2f69fbccc3fb4be4fd/femovol.pdfIn PDF document text
    • https://idosekotthonaveresegyhaz.hu/files/files/6517211347.pdfIn PDF document text
    • http://sweetbasketsbyjackie.com/clients/864293/File/77875242755.pdfIn PDF document text
    • http://www.sparkprototypes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b25ca43c60f---tojadoxefujojat.pdfIn PDF document text
    • https://www.lindopoint.it/wp-content/plugins/super-forms/uploads/php/files/7b34b530d30247395695edd5f02cd56f/73369546207.pdfIn PDF document text
    • https://rockyshairsalon.com/wp-content/plugins/super-forms/uploads/php/files/ukqmssl4jt8af3n5ambuok6j41/72677369048.pdfIn PDF document text
    • https://www.d-table.com/wp-content/plugins/super-forms/uploads/php/files/193e814dce45f32fe17e751a3d5c7f26/81235123103.pdfIn PDF document text
    • https://rarahil.org.np/ckfinder/userfiles/files/52665249975.pdfIn PDF document text
    • http://gotoippc.com/ckfinder/userfiles/files/narekaronepofunupoxamef.pdfIn PDF document text
    • http://www.hotel-margherita.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612a846e88802---walux.pdfIn PDF document text
    • http://laweasy.kr/userfiles/file/lobovisolededotomonoza.pdfIn PDF document text
    • https://chuyennhakienvangvn.net/upload/files/ludozadurefan.pdfIn PDF document text
    • https://ph2020.org/ckfinder/userfiles/files/96627765877.pdfIn PDF document text
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160b8f171c4e39---vizufubigeripisibipifik.pdfIn PDF document text
    • http://kurier48.pl/files/userfiles/file/gizelako.pdfIn PDF document text
    • http://turar-mussin.com/userfiles/File/gatidewotix.pdfIn PDF document text
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f4dae10cfd---kamedajepixebox.pdfIn PDF document text
    • https://theatresaucinema.fr/uploads/file/gurojenup.pdfIn PDF document text
    • http://ashioke.com/images/library/File/50955484827.pdfIn PDF document text
    • https://srp-galabau-rostock.de/wp-content/plugins/super-forms/uploads/php/files/7qvg8sc500ro6l8demfrlhdadj/bumalugemefadisowajolobo.pdfIn PDF document text
    • https://www.electriclighting.com/wp-content/plugins/super-forms/uploads/php/files/f0ee596b4f4cd6a22fa0b60c4c363211/37371175451.pdfIn PDF document text
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/4425962516b6fa9dbba8367194694e8e/88161846393.pdfIn PDF document text
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607b9032b2bdf---kisorowud.pdfIn PDF document text
    • http://sandsflooring.co.uk/ckfinder/userfiles/files/29879220766.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=electroanalytical+sensors+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_off0000f289.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF289 18440 bytes
SHA-256: 8b198bdf923075ccd19b01cdec20825fb4bfd19ccdf2267c89747ef230bc8d93
font_01_sfnt_off0001229b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1229B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013ab2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13AB2 10708 bytes
SHA-256: e5fbae9e57b24a7ceec42e9daf7bc0aab99ccd3158f1306a1683f078c2977576