Malicious PDF — malware analysis report

Static analysis result for SHA-256 b56c4c923ae0717e…

MALICIOUS

PDF

73.1 KB Created: 2021-09-06 15:31:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 4a36e5569b9134338f8ce38499011db9 SHA-1: 685a3760aab3b7e1085c12728820caa515d39207 SHA-256: b56c4c923ae0717ea52839791915e00315c4bef518ef0ddbbf08708e0f8c2b61
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress upload directories or disposable hosting, indicating a link farm designed to redirect users to potentially malicious sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://wittnebel.dk/file/31154907103.pdf In PDF document text
    • http://instandee.com/Images_upload/files/telobisuxavexevax.pdfIn PDF document text
    • http://linza-market.ru/upload/files/xorunepefowalobijubufuj.pdfIn PDF document text
    • https://sklep-pinokio.pl/web/uploads/files/kubusizoz.pdfIn PDF document text
    • http://health-bridge.in/upload/file/dazobiluwenimini.pdfIn PDF document text
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad929e2ebce---12622999557.pdfIn PDF document text
    • https://www.paparazzirestaurant.com.au/wp-content/plugins/super-forms/uploads/php/files/d16a0a43a4d84d9eb8d14144ab132efa/delafiz.pdfIn PDF document text
    • https://carpanea.it/wp-content/plugins/super-forms/uploads/php/files/2c113c20aee140658ef8c430396434d8/ritimefikuke.pdfIn PDF document text
    • https://caribemed.com/userfiles/file/mukegazamus.pdfIn PDF document text
    • http://findusafranchise.com/files/files/fosefokepese.pdfIn PDF document text
    • http://bigxra.com/uploadfile/file/2021051201595873499.pdfIn PDF document text
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/160876dbd82df2---xedopogizaledunej.pdfIn PDF document text
    • http://sad-azov.ru/wp-content/plugins/super-forms/uploads/php/files/b7d87338210fed71cde1ef8fc2aa0e70/wakatalodewaxepukagod.pdfIn PDF document text
    • http://ahkjt.com/upfile/file/bizozaz.pdfIn PDF document text
    • http://fantasypartyentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e555cdc3ae5---rakuzelurupuxituk.pdfIn PDF document text
    • https://ms02bet.com/contents//files/26715045816.pdfIn PDF document text
    • http://mansiya.com/uploadfile/files/31814228907.pdfIn PDF document text
    • http://francescasciortino.it/userfiles/files/nuladorulasabinu.pdfIn PDF document text
    • http://martonaroniskola.net/userfiles/file/48273863427.pdfIn PDF document text
    • https://www.parkgest.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16085284123322---24570094337.pdfIn PDF document text
    • https://bostoncake888.com/UserFiles/files/lonudaxem.pdfIn PDF document text
    • http://gaziogluenerji.com/images_upload/files/64073872833.pdfIn PDF document text
    • http://jfk1969nola.com/clients/873000/File/tawexurizewumojafu.pdfIn PDF document text
    • http://olneyjune65.com/clients/d/dc/dcef5d22f85ec69f5810ba62c2e8cf46/File/xizebozetudelesijada.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=unwanted+book+1+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_off0000bac4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBAC4 17120 bytes
SHA-256: b9774337844a4ef878c39aa15b7d391c735cd8cd6cb70c698a9d7d9e98601936
font_01_sfnt_off0000e718.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE718 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ff2f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF2F 10460 bytes
SHA-256: 9a518120be2c13ab6f48876a378468bcaffbc2aace7d49d8a179508e8ab79c8b