Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4da1b63dec8383a…

MALICIOUS

PDF

81.0 KB Created: 2021-09-01 08:01:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 3238ae2dbde57f8de54f559c6e8ccd5b SHA-1: 38d3650bf5f84dcd12dea4498c5a0c62bae26ec8 SHA-256: c4da1b63dec8383a90ced2c164c8f9671a9370b4c4f81c075b647b833249ac9b
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains a link farm pointing to multiple compromised websites, identified by heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM'. These links likely serve as a distribution mechanism for malicious content or phishing pages. No scripts were extracted, and the document body was unreadable, limiting further analysis of specific payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

Heuristics 5

  • 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://bwc.lt/i/12788845560.pdf In PDF document text
    • https://eliteswimmingpoolsinc.com/wp-content/plugins/super-forms/uploads/php/files/r1e2beidlo4jq2neaio92jupj5/zibawomazanomonibi.pdfIn PDF document text
    • http://plusbateria.com/wp-content/plugins/formcraft/file-upload/server/content/files/161247eaf02882---pofuboke.pdfIn PDF document text
    • https://tahitotfaluovodak.hu/ckfinder/userfiles/files/wopizodubegugavejupotema.pdfIn PDF document text
    • http://www.realisthotel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ce14cc600a8---29065184276.pdfIn PDF document text
    • https://apteka-wratislavia.pl/halatecza/userfiles/file/nenawuxoropamisagejasapob.pdfIn PDF document text
    • http://hnc2.com/userfiles/file/59397511692.pdfIn PDF document text
    • https://armagedonspedycja.pl/files/file/nipixesexutadujupig.pdfIn PDF document text
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/160a1da11e94f9---56405822489.pdfIn PDF document text
    • http://rapet.hu/files/8966818682.pdfIn PDF document text
    • http://kiuanai.com/userfiles/file/98077155662.pdfIn PDF document text
    • http://nuestratierrapremios.com/campannas/file/talavovuni.pdfIn PDF document text
    • http://obasekiestates.com/UserFiles/file/89250379569.pdfIn PDF document text
    • https://2winit.com/Files/files/12329070291.pdfIn PDF document text
    • https://lesura.net/userfiles/file/90067246407.pdfIn PDF document text
    • http://seoulmenu.com/uploads/files/17137467963.pdfIn PDF document text
    • http://domkomplekt34.ru/attachments/file/zerosisanasivozuxenozopi.pdfIn PDF document text
    • https://hgb.se/filer/file/78416891559.pdfIn PDF document text
    • https://aldapa.eus/files/galeria/files/26359119880.pdfIn PDF document text
    • http://archimax.ch/dynamic-images/cms/file/1925250870.pdfIn PDF document text
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c5613d09656---lodutujutuxevogararijoja.pdfIn PDF document text
    • https://sheenabusesandcoaches.com/userfiles/file/tedogebepeneguriruloxabe.pdfIn PDF document text
    • https://chetanaus.org/bheru/uploadfiles/file/96880423201.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=after+thawing+chicken+how+long+can+it+stay+in+the+fridgePDF 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_off0000d6ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6CE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000eee0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEE0 17644 bytes
SHA-256: b76bbc5b0f2074c171171aa89fde42407c203bc17f951ce9fec3a5f28f9a8a11
font_02_sfnt_off00011c92.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C92 11028 bytes
SHA-256: d2dfd0bd57eb0922c372114f5e0fbe31bc115dd68f68237f91e234af0f04e41e