Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb69df1da9faffeb…

MALICIOUS

PDF

84.7 KB Created: 2021-09-06 00:17:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 787a7f0a216a4c089104fa5dc4409561 SHA-1: 7f9c56a9b02da923608015ef9b22d71984daa3cb SHA-256: cb69df1da9faffebe4e6728e1cf8153c487955d054c7a898546313a580ab3a33
156 Risk Score

Malware Insights

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

The file was detected 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 CMS upload storage locations. The presence of numerous unknown URLs suggests a phishing or malware distribution campaign.

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 http://www.advokat.com/app/webroot/img/fck/file/mabexadavesiraxatonuxed.pdf In PDF document text
    • https://studiogreenwich.ru/wp-content/plugins/super-forms/uploads/php/files/af2dec20509de1a94119cd91de4ff757/parotazawowinavosu.pdfIn PDF document text
    • https://maidintown.co.uk/wp-content/plugins/super-forms/uploads/php/files/2be7ea04d1e75887485ff1e39439ece5/pesosadodixufo.pdfIn PDF document text
    • https://prairieroseclothiers.com/FCKeditor/file/7738613.pdfIn PDF document text
    • http://ourgans.org/userfiles/files/powugidogu.pdfIn PDF document text
    • https://www.superioreagle.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4ae328c726---tonagufiz.pdfIn PDF document text
    • https://eduinfinite.com/wp-content/plugins/super-forms/uploads/php/files/e4fe3b6e9fedd6222fcfe9502c8b0f45/4061084150.pdfIn PDF document text
    • https://abzesolar.com/uploads/files/56627610941.pdfIn PDF document text
    • https://globalmediaminds.com/uploads/files/17661392275.pdfIn PDF document text
    • http://crediramasrl.it/public/file/31394116840.pdfIn PDF document text
    • http://doudou.tw/userfiles/files/90273231999.pdfIn PDF document text
    • http://www.zav-mito.si/wp-content/plugins/formcraft/file-upload/server/content/files/160f04f43c0ff9---52826663572.pdfIn PDF document text
    • http://biomassasia.net/data_ed/userfiles/file/dukutunewu.pdfIn PDF document text
    • http://indago-rovigo.it/userfiles/files/soduzijozaz.pdfIn PDF document text
    • http://nuestratierrapremios.com/campannas/file/kevixerejigeruvopibagowi.pdfIn PDF document text
    • http://reichspfarrer.sk/file/78804816236.pdfIn PDF document text
    • http://hosungtour.net/FileData/ckfinder/files/20210706_AFAFDAA71D5CFDA1.pdfIn PDF document text
    • https://sbsoftware.ro/admin/userfiles/file/gavetudoxikipenamuda.pdfIn PDF document text
    • https://anzmrrn.org/wp-content/plugins/formcraft/file-upload/server/content/files/16095042b2bff4---wunutosobeguvu.pdfIn PDF document text
    • https://shared401k.com/wp-content/plugins/super-forms/uploads/php/files/3eefae43e9e7ab2e779ea7ead6ca3748/12136228002.pdfIn PDF document text
    • https://www.poolsrus.com.au/application/third_party/ckfinder/userfiles/files/95748535224.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=organismos+descomponedores+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_off0000e1f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1F7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fa09.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA09 20584 bytes
SHA-256: 3b255489e7b228099cf97c9b13981dfa508a4bb09d3e892cc92e7166ac345b36
font_02_sfnt_off00012c64.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C64 10844 bytes
SHA-256: bd8757c20abb4a0c934a77ae00c65c4ed78d56a79fb68311ff665a4316a125e1