Malicious PDF — malware analysis report

Static analysis result for SHA-256 238b506315c5cc7e…

MALICIOUS

PDF

89.1 KB Created: 2021-07-04 14:48:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: b4ef1952e52bb9c81f95d1fb0cfc1143 SHA-1: baf57135801940f4467ad0c33d23792cd1234207 SHA-256: 238b506315c5cc7ecd2629d7a35ea7addfe00658c51718fd5c18a9599a37b3bf
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of links, many of which point to compromised WordPress upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is unreadable, but the link farm heuristic and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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 http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/16071bdbd97fcc---vixotivofodizemiwexexof.pdf In PDF document text
    • http://vickerycarpet.com/uploads/images//files/metibefakezoxunewifozaje.pdfIn PDF document text
    • http://asu.com.vn/wp-content/plugins/super-forms/uploads/php/files/vk35rvm7ojfrl4q3v712oltv83/32024517984.pdfIn PDF document text
    • https://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a8dc270fec9---73983169967.pdfIn PDF document text
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607363b896f63---14902344069.pdfIn PDF document text
    • http://josephfellerlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/nubufabumivaruxowevu.pdfIn PDF document text
    • http://oreade-breche.fr/userfiles/file/fofuzitotusoxowurazel.pdfIn PDF document text
    • https://igruppe.no/ckfinder/userfiles//files/fivepajelof.pdfIn PDF document text
    • http://julieesteban.com/wp-content/plugins/formcraft/file-upload/server/content/files/160afd44adaed5---43573433482.pdfIn PDF document text
    • http://www.maarsehoveniers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608fc90e4c808---1198517518.pdfIn PDF document text
    • http://aeskulap24h.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080f2a99b562---59635884951.pdfIn PDF document text
    • http://tsg-vaganovskoe.ru/ckfinder/userfiles/files/vozatulalabinikavameme.pdfIn PDF document text
    • http://pillshop.ru/uimg/files/73624648351.pdfIn PDF document text
    • https://autoschiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608f689445a89---21744294527.pdfIn PDF document text
    • https://kopari.hu/files/file/1206885851.pdfIn PDF document text
    • https://coil.hk/upload/files/4169488852.pdfIn PDF document text
    • https://gdr.co.il/wp-content/plugins/super-forms/uploads/php/files/84c330c91db5352e44105231698c62f8/womuzijejazubupenuduwaso.pdfIn PDF document text
    • https://broodjedenbosch.nl/ckfinder/userfiles/files/jegozebixurigisike.pdfIn PDF document text
    • http://dichvu12h.net/userfiles/file/zixoz.pdfIn PDF document text
    • https://accesoriosalmayor.com/images/userfiles/file/wevuwelilosopikerunolewe.pdfIn PDF document text
    • https://promocionesnma.com/wp-content/plugins/super-forms/uploads/php/files/eded8e4604917585ad2a027f5acc40d7/rawetaduf.pdfIn PDF document text
    • http://laiyi-art.com/userfiles/file/58682027927.pdfIn PDF document text
    • http://www.benvenutialmare.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cbd6bc5409---dulenazaxuserik.pdfIn PDF document text
    • https://tehnol.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608b61cd49f4a---guwuwevedid.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=love+is+powerful+essayPDF 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_off0000fafd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAFD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011314.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11314 10472 bytes
SHA-256: baadf97b6537cff4d069f93a0282b13feed16583ee74115c2f328c7191685b53
font_02_sfnt_off00012b16.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B16 16952 bytes
SHA-256: f22a9f945064c3c55ad083dbb2679feee5164926738e1bbb0b0a1a80650a4044