Malicious PDF — malware analysis report

Static analysis result for SHA-256 21e3ff6e259e8336…

MALICIOUS

PDF

82.2 KB Created: 2021-06-19 19:49:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: 1db92483d475be434b504ab5d27eced1 SHA-1: 0f8e31068005099552340decd536836764cd2e40 SHA-256: 21e3ff6e259e83362f26eded6af40802591a77a8c84d617ec13ad84d5c3b439f
96 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or appear to be part of a link farm. The ML classifier strongly indicates maliciousness, and the structure suggests an attempt to lure users to potentially malicious or SEO-manipulated content. No scripts were extracted, limiting the analysis of direct execution vectors.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/ca361978adeeea45ff8c7377972ef31d/vevusagaremisamifekujogab.pdf In PDF document text
    • http://voszveszprem.hu/_user/file/vilisavolipomenotam.pdfIn PDF document text
    • http://royalwedding.jp/images/blog//file/mebegulupukipixowugub.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb10308b54---37322388877.pdfIn PDF document text
    • http://visualpaint.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cbd0dd6111e---88794844199.pdfIn PDF document text
    • http://taborcapitalpayment.com/clients/d/d0/d0a3925ee25d0adc8806453b18bccccc/File/66995142136.pdfIn PDF document text
    • http://www.gaviprintpack.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c69f863c045---13462540346.pdfIn PDF document text
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b6247b5ab02---15976057530.pdfIn PDF document text
    • http://wisdomtours.net/upload/file/wiworu.pdfIn PDF document text
    • https://www.makathastaliklari.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607c1ea26e6cc---ronagapibudodedewun.pdfIn PDF document text
    • http://lookupagency.es/wp-content/plugins/formcraft/file-upload/server/content/files/1608a6768f17d7---78594010273.pdfIn PDF document text
    • https://law.myvzl.com/wp-content/plugins/super-forms/uploads/php/files/kqobq3395as4j2g1ji7gkac16j/rusogijabadogumenaper.pdfIn PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/h6nn3di5konnlm5vb9ib35o70a/junorigapor.pdfIn PDF document text
    • https://aymsoft.us/aym_image/files/vaweboraluzamigipaza.pdfIn PDF document text
    • http://hi-reid-solutions.com/wp-content/plugins/super-forms/uploads/php/files/87e5d89dd829c0777979636211c895dc/pubuduzuwinozurakuxojuweg.pdfIn PDF document text
    • http://fedorahosted.org/lohitIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=turistas+movie+download+in+tamil+dubbed+isaiminiPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_004_off0000f909.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0xF909 11840 bytes
SHA-256: 354ac17483dbddef29a05e8ad3ee1a63a168b6c9e38da171552945c94b3576d6
font_00_sfnt_off0000e759.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE759 5212 bytes
SHA-256: 8d49be9a154bfe669e72c6bba6e106fa59f721c60a93fd875b9b76e7f0067338
font_02_sfnt_off00011777.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11777 10368 bytes
SHA-256: 3b690577a687f69a450cf16baa530b5f9508903bf7e6110a7b3ba8231d5bd9f9