Malicious PDF — malware analysis report

Static analysis result for SHA-256 59537b5781cf1124…

MALICIOUS

PDF

82.5 KB Created: 2021-09-08 02:45:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: c9a49a37a2c8740898e41d6d830f7ab1 SHA-1: a2461be0beae00cfbf5e279dfc8023e02836e177 SHA-256: 59537b5781cf11242fb8e20f95d9aa2669cc6e4f6e6aec545ddd858fec3f95e9
156 Risk Score

Malware Insights

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

The PDF was flagged by multiple heuristics as a link farm, with many URLs pointing to potentially compromised CMS upload directories. The ML classifier and ClamAV also strongly indicated maliciousness, specifically identifying it as a phishing trojan. The document body is unreadable, but the presence of numerous external links suggests an attempt to redirect the user to malicious sites.

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://myucmas.com/userfiles/file/juxuzexetupogulologasaz.pdf In PDF document text
    • http://www.shipsupply.co.mz/wp-content/plugins/formcraft/file-upload/server/content/files/160a2063b022ae---xevovixevavosine.pdfIn PDF document text
    • http://www.predoisiasociatii.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a47f340a30f---nubuzu.pdfIn PDF document text
    • https://www.peltonfell.org.uk/ckfinder/userfiles/files/vibibapavazupib.pdfIn PDF document text
    • http://lelit.nl/app/webroot/files/userfiles/files/kumixote.pdfIn PDF document text
    • https://bibliothequeanglaise.org/upload/files/95724260502.pdfIn PDF document text
    • http://24hnbc.com/assets/ckfinder/core/connector/php/uploads/files/jirakatewugapu.pdfIn PDF document text
    • https://purevdavaa.mn/uploads/ckfinder/files/rifafodid.pdfIn PDF document text
    • http://areaengineeringsrl.eu/userfiles/files/90627789838.pdfIn PDF document text
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/fadca2ede5bae82fe90733074f35c287/60539241617.pdfIn PDF document text
    • http://highgaincomposites.com/img/file/2021621225720.pdfIn PDF document text
    • https://glycocalyx.nl/userfiles/image/file/laxegojifaxuma.pdfIn PDF document text
    • https://sportsht.com/userfiles/file/raravunivatisavix.pdfIn PDF document text
    • https://www.pessin-location.fr/ckfinder/userfiles/files/zisafeduxelabufudilis.pdfIn PDF document text
    • http://www.ambredore.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609be9752a47b---zodekosolapixajaxasajuna.pdfIn PDF document text
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bcb050771fe---fijek.pdfIn PDF document text
    • http://telekommarketing.com/firme_data/files/fipumakibuzojovukivur.pdfIn PDF document text
    • http://ankurgroups.com/userfiles/file/43996548123.pdfIn PDF document text
    • https://allegypttours.net/userfiles/files/parixevo.pdfIn PDF document text
    • https://bandotrading.it/uploads/file/59590733475.pdfIn PDF document text
    • http://studiopetrilli.it/userfiles/files/molabilijefoxuxutototo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=nombres+biblicos+para+ni%C3%B1os+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_off0000d971.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD971 11008 bytes
SHA-256: 8b9724b0860fe1312ed600c7de3536e6245d6fe674341cf8a182dfec9a690067
font_01_sfnt_off0000f277.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF277 19076 bytes
SHA-256: 4579c8500ae4c27c57682ac6a6be4867f21c81f78b87e9df262666a2db14ee5e
font_02_sfnt_off00012206.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12206 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1