Malicious PDF — malware analysis report

Static analysis result for SHA-256 53320c5b8b5167c5…

MALICIOUS

PDF

73.0 KB Created: 2021-09-01 10:58:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: cf3e37fcbfc6cbab2d400294b38878b8 SHA-1: 27e27516c7c3d616974d33b93057c3816159d174 SHA-256: 53320c5b8b5167c5be084256868570c50c226c21f64a83a0ce35486d5d52331f
156 Risk Score

Malware Insights

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

The PDF file contains a link farm with numerous URLs, several of which point to compromised WordPress upload directories. The ML classifier and ClamAV detection strongly indicate maliciousness, classifying it as a phishing trojan. The primary function appears to be redirecting users to potentially malicious content hosted on various domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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 https://marljivo.hr/userfiles/file/sutiteriwinelaperafiruvu.pdf In PDF document text
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/a4e034c2bae0a4636d766f6e47675b11/javalixidufipulijitivimux.pdfIn PDF document text
    • http://t-eamplus.de/web/editor/files/55549273254.pdfIn PDF document text
    • http://envisystem.com/upload/userfile/files/63887196554.pdfIn PDF document text
    • http://berallebags.com/UploadFiles/FCKeditor/20210731121437.pdfIn PDF document text
    • http://alconburyreunion.com/clients/36523/File/jezuporunove.pdfIn PDF document text
    • http://vibrosystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1609b4428191af---23815907217.pdfIn PDF document text
    • https://istanajp2.com/contents//files/6153801308.pdfIn PDF document text
    • http://terhautz.com/upload_files/files/19253052827.pdfIn PDF document text
    • http://alexlunacoach.com/img/editor/file/23379755777.pdfIn PDF document text
    • http://clinicaveterinariasangiacomo.it/userfiles/files/79883397201.pdfIn PDF document text
    • http://sushikyototogo.com/uploads/files/54686195937.pdfIn PDF document text
    • https://nhachoxebus.com/upload/fck/file/xonuruvuxurojibaxurot.pdfIn PDF document text
    • http://fortlauderdalelimorental.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607049809b8d2---10742416529.pdfIn PDF document text
    • https://drddvichitra.com/userfiles/file/91040752838.pdfIn PDF document text
    • http://bumsnab.ru/uploads/files/82697334776.pdfIn PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/sghqmshd46j299n8h72qoup46o/51281309490.pdfIn PDF document text
    • https://www.goldenplanet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160a77e2aae8f0---74905793547.pdfIn PDF document text
    • https://laxmigrouppune.com/wp-content/plugins/super-forms/uploads/php/files/236cdf19d7cbff1d5d400158dcfe6c38/bifowujowebiletekuwisaba.pdfIn PDF document text
    • https://hostmegasoft.com/calisma2/files/uploads/dotuzaxukijuxasapew.pdfIn PDF document text
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160835a229a30c---xujotuzewajomojunem.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=all+hallows+secondary+schoolPDF 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_off0000bda2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBDA2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d5b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5B9 10456 bytes
SHA-256: 7af795ab57a248385a68f586fb1393feedadf0f1040079a10256842fadeba248
font_02_sfnt_off0000ed85.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED85 16172 bytes
SHA-256: e53aeeafe1978e54f6cb31b1ed2f9759c47b27f3f579e36203adf52c3198511c