Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd441efc13fa68f0…

MALICIOUS

PDF

97.0 KB Created: 2021-08-10 09:01:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-16
MD5: 33f6fc368ab8a82afbfd27d6dc2d605f SHA-1: cd765c883a93492b0f35a2f0657036aef139fb3b SHA-256: cd441efc13fa68f039909cd2f51099ce5058226681273e14039eaca720276c18
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to numerous external URLs, many hosted on compromised WordPress sites or disposable domains. The embedded URLs and the overall structure suggest a phishing or malware distribution campaign, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9979

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://krisoc.ru/uplcv?utm_term=balancing+redox+reactions+worksheet+2+answer+key PDF link annotation
    • https://cicadit.ro/UserFiles/file/42095191083.pdfIn PDF document text
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1138044758---54647572188.pdfIn PDF document text
    • https://ludifrance.fr/userfiles/file/vogofegekafuvitimutazavi.pdfIn PDF document text
    • https://rajakeempat.com/contents//files/temulegexefekar.pdfIn PDF document text
    • https://cbolean.com/wp-content/plugins/super-forms/uploads/php/files/9ip4l2cm4e2us6aib9au0tvrl1/teliva.pdfIn PDF document text
    • http://drkoopman.nl/cmsimages/file/gedixapiwiv.pdfIn PDF document text
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9d97239fa---74785126871.pdfIn PDF document text
    • https://tcremich.lu/files/files/64560267813.pdfIn PDF document text
    • https://kiaavcilar.com/upload/ckfinder/files/68491792785.pdfIn PDF document text
    • https://acgroupenterprise.com/userfiles/file/11378139788.pdfIn PDF document text
    • http://drapa-technika.cz/UserFiles/File/2238223870.pdfIn PDF document text
    • https://www.hotwaterfactory.com.au/wp-content/plugins/super-forms/uploads/php/files/73204426745cdb33ac5cab2addf48905/bekikexotojil.pdfIn PDF document text
    • http://sjar-tech.com/uploadfile/file///2021060622142065.pdfIn PDF document text
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607785e4431f9---8249559307.pdfIn PDF document text
    • https://vadihosting.com/calisma2/files/uploads/7627205558.pdfIn PDF document text
    • https://biothiennam.com/media/ftp/file/verozagojap.pdfIn PDF document text
    • https://www.siemers-deutschmann.de/wp-content/plugins/super-forms/uploads/php/files/rpinelimuei7vt8carjikqvvji/27140979551.pdfIn PDF document text
    • http://baanpowertrain.com/wp-content/plugins/formcraft/file-upload/server/content/files/16111b33604cc0---5839861705.pdfIn PDF document text
    • http://hotelclinton.it/userfiles/files/42626419758.pdfIn PDF document text
    • https://anzmrrn.org/wp-content/plugins/formcraft/file-upload/server/content/files/160cd577c53f15---losoviluriba.pdfIn PDF document text
    • http://aryajob.com/user_upload/file/66554182141.pdfIn PDF document text
    • http://beytarimcilik.com/admin/editor_resim/file/doronolisitutakixezek.pdfIn PDF document text
    • http://domosplast.hu/files/file/bejukavomepope.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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fd79.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD79 16084 bytes
SHA-256: 4e8a04f4a78fa3afc58a57d2cac5c2e1f8bf6776ecd71fe0ca93f3ac5299143c
font_01_sfnt_off000112a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112A5 17584 bytes
SHA-256: 33116fee1926d4c69e9ddc9f9636e4fc6d3d324b7cebfee56db0654e467442a0
font_02_sfnt_off00014113.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14113 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_03_sfnt_off0001592a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1592A 11216 bytes
SHA-256: 2b429d9cff0b6c50df0b0268e12fcf02bb72aacbecd992f72ef2ad2988b6cbe9

Open this report in the interactive analyzer, or submit your own file for analysis.