Malicious PDF — malware analysis report

Static analysis result for SHA-256 739a3563f1b3f709…

MALICIOUS

PDF

81.9 KB Created: 2021-09-16 10:22:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 3dbfa7d9fbd74f35375a782709c7f15c SHA-1: 209f0b57432b4f60309cb15424ca5fd8bdc8c34b SHA-256: 739a3563f1b3f709d09efeb404c3983f32b9dc95c0ca8f2acb91cae13fdae386
96 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised WordPress sites, suggesting an attempt to distribute malicious content or phish users. The ML classifier strongly indicated maliciousness. While no scripts were extracted, the structure and embedded URLs point towards a malicious document designed to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://raduzhniy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613031d1775e2---fojavibojadajufatotuk.pdf In PDF document text
    • https://guruvinodji.com/Userfiles/file/12198934489.pdfIn PDF document text
    • http://sinara.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1614044f9d9d5e---17232702509.pdfIn PDF document text
    • https://purpleleafestatebuyers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fcc2cec95c---44676690948.pdfIn PDF document text
    • http://unipsyclinic.com/userfiles/file/20210905221424.pdfIn PDF document text
    • http://www.canadiantreasurer.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d6d329b639---zasafafaro.pdfIn PDF document text
    • http://yongqingtech.com/d/files/91205814725.pdfIn PDF document text
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/1614151d18829f---dorizasebelegixevagil.pdfIn PDF document text
    • http://sromedical.com/file_media/file_image/file/66287844088.pdfIn PDF document text
    • https://rougezenekar.hu/files/file/23994202671.pdfIn PDF document text
    • https://ruxthai-guesthouse-chiangmai.com/ckfinder/userfiles/files/78739567559.pdfIn PDF document text
    • http://gachtrangtritranvinhtin.com/gachtrangtritranvinhtin/Images_upload/files/mowowisupovinegipu.pdfIn PDF document text
    • https://daulte.com/ckfinder/userfiles/files/taxebejodatibizipibedavav.pdfIn PDF document text
    • http://nepodoshlo.kz/ckfinder/userfiles/files/58338481283.pdfIn PDF document text
    • http://premiercontainerlines.com/media/ftp/file/vefisop.pdfIn PDF document text
    • https://gianlucabruno.it/dati/upload/file/65105012323.pdfIn PDF document text
    • https://sunpower.lv/ckfinder/userfiles/files/24703814583.pdfIn PDF document text
    • http://sky1981.com/asset/uploads/files/vekisum.pdfIn PDF document text
    • https://nilsahost.com/calisma2/files/uploads/vedebipemujupiv.pdfIn PDF document text
    • http://acril.ru/ufiles/files/40063554414.pdfIn PDF document text
    • http://unite-chem.cn/upload/files/zinelomonifoxi.pdfIn PDF document text
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614280c137a80---78459537977.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=how+to+force+stop+appsPDF 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_off0000dcc2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCC2 17800 bytes
SHA-256: 5cdfe5a40e74307fa4051d9538dc3be9b94eecb219906a67534dc10ecbb1e821
font_01_sfnt_off00010a6b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A6B 10308 bytes
SHA-256: 16d144ecbaaecc07258ee7286c9c7110032452da20eb26c9594d61828b75ccf0
font_02_sfnt_off000121e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121E0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1