Malicious PDF — malware analysis report

Static analysis result for SHA-256 dcd9516438e82214…

MALICIOUS

PDF

77.8 KB Created: 2021-06-27 15:06:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 73a97315c7b6a0a45f1b7ac46e5bd266 SHA-1: ca3a001fa70bd329e602774cd54af940aaff8086 SHA-256: dcd9516438e82214cf86e4b77898555e1659f73eb3166b64d3901c40013daf4f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to compromised WordPress sites and other disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. Although no scripts were explicitly extracted, the nature of the URLs and the heuristic firings point towards a malicious document, potentially leveraging embedded JavaScript for redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://catamma.ru/uplcv?utm_term=commas+and+apostrophes+worksheets PDF link annotation
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1609e2bf8bfc22---jifomirujiwofekunipo.pdfIn PDF document text
    • http://bamt.be/wp-content/plugins/formcraft/file-upload/server/content/files/16094fc1da310e---47918972779.pdfIn PDF document text
    • http://sun-green.nl/ckfinder/userfiles/files/sizakajafinomubegawewup.pdfIn PDF document text
    • https://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072bc4a227b1---japeparek.pdfIn PDF document text
    • http://www.asejnrtigers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160c5677771ea1---1864742681.pdfIn PDF document text
    • http://www.majorisinvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606f5f4308d06---81720861411.pdfIn PDF document text
    • https://kop-trans.pl/uploads/userfiles/files/begiram.pdfIn PDF document text
    • http://parkwestresidences.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b65aab8489---91474909812.pdfIn PDF document text
    • https://insights3.com/wp-content/plugins/super-forms/uploads/php/files/07c0ad54431558fdfc0f4e47764569c6/42759649242.pdfIn PDF document text
    • http://www.predoisiasociatii.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160d648584ec23---foxixidarep.pdfIn PDF document text
    • http://ksuskalology.com/images/file/86602911459.pdfIn PDF document text
    • http://okzawidow.pl/img/upload/files/vixufi.pdfIn PDF document text
    • http://cameronhaddock.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be461788943---11399413181.pdfIn PDF document text
    • https://harpethvalleypto.org/wp-content/plugins/super-forms/uploads/php/files/8e7ea3b489ac5605ea102308df685e3f/zujidadefadokisalevizoka.pdfIn PDF document text
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1606d06cc0b10f---7478525814.pdfIn PDF document text
    • https://echipamente-scule.ro/userfiles/file/pufarujigimuturiledumu.pdfIn PDF document text
    • https://burlingame.com/wysiwygfiles/file/vubenunoromufimiwa.pdfIn PDF document text
    • https://ewms.vn/wp-content/plugins/super-forms/uploads/php/files/4aebdfpmbjso14grh6vhu8llnk/xedisigozuk.pdfIn PDF document text
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16083e1d36ee0a---mumazujapesumejoxakij.pdfIn PDF document text
    • http://endustriyelkiralama.com/wp-content/plugins/super-forms/uploads/php/files/e76bjr3uhsclcreel6dcfcg1mi/vevolupixa.pdfIn PDF document text
    • https://nacionalequipamentos.com/ckeditor/uploads/files/93629176459.pdfIn PDF document text
    • https://www.vedaaz.com/wp-content/plugins/super-forms/uploads/php/files/12b7233e049055f063b16c038db79487/29169919345.pdfIn PDF document text
    • http://emanuelmlevin.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/6572269651.pdfIn PDF document text
    • http://ceramicaartisticamarsalese.it/userfiles/files/32945102821.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_off0000cd52.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD52 16376 bytes
SHA-256: 95e9b11e9c1ce25242858ae577a007ea645f9efa0a4438ca1eef05dc749c27f9
font_01_sfnt_off0000f79a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF79A 10728 bytes
SHA-256: 390c57101a100b0fb983229cd1f03c60c1b0cd3adcf88e67d81b62a3282f3ce2
font_02_sfnt_off00011027.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11027 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1