Malicious PDF — malware analysis report

Static analysis result for SHA-256 f6f7c59812e0d9bc…

MALICIOUS

PDF

100.6 KB Created: 2021-05-23 09:06:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 52b89d6121ded0fcba21ce48d3906679 SHA-1: b594d321efa66dcddf6d775caf247d8338e3a3b5 SHA-256: f6f7c59812e0d9bc97793529ec7499689216983795d0374bfd394a7ee9e29884
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains a large number of external links, many pointing to disposable hosting, suggesting a link farm or SEO manipulation tactic. The presence of embedded URLs and the heuristic 'PDF_SEO_LINK_FARM' strongly suggest the document's primary purpose is to redirect users to potentially harmful external sites, possibly for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://golowaki.ru/strik?utm_term=dividing+mixed+fractions+worksheet+with+answers PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4456989/normal_604ceb751abc3.pdfIn PDF document text
    • https://wefidabewurar.weebly.com/uploads/1/3/1/1/131164485/51010463efb612.pdfIn PDF document text
    • https://lolijizaw.weebly.com/uploads/1/3/4/4/134461821/pinotetuxinap_ruvodamu_miran.pdfIn PDF document text
    • https://nunipotewisi.weebly.com/uploads/1/3/4/8/134892443/9078165.pdfIn PDF document text
    • https://gisunotagalaros.weebly.com/uploads/1/3/2/3/132303086/jajozun.pdfIn PDF document text
    • https://ninuxegomozul.weebly.com/uploads/1/3/1/8/131871835/mamigijufal.pdfIn PDF document text
    • https://funifagokose.weebly.com/uploads/1/3/2/6/132681236/zoriri.pdfIn PDF document text
    • https://legovizadedugid.weebly.com/uploads/1/3/1/8/131856283/b423e5f.pdfIn PDF document text
    • https://junimadegerozo.weebly.com/uploads/1/3/4/0/134096607/b217d6fd87.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4421217/normal_6058f4c716662.pdfIn PDF document text
    • https://numezuledidi.weebly.com/uploads/1/3/4/0/134096646/zoxuwuvo-mutegejet.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4479678/normal_5fda07537e0b0.pdfIn PDF document text
    • https://xetibipu.weebly.com/uploads/1/3/4/5/134528590/vifut.pdfIn PDF document text
    • https://danulezide.weebly.com/uploads/1/3/4/6/134601395/2559561.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4413966/normal_606bc572c43a5.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4411921/normal_603d4882b3be2.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/3429734f-2d38-4d15-88e9-65a4e82b27db/mifukodizoki.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/51d22098-f9c9-47ac-a4ac-cbd9b81111fe/ejemplos_de_verbos_regulares_en_ingles_en_tiempo_pasado.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cde176a7-7cf4-4fd0-8d3b-69b9dcc8f31a/dakom.pdfIn PDF document text
    • https://s3.amazonaws.com/fosagobomap/luwoxudamipigi.pdfIn PDF document text
    • https://s3.amazonaws.com/dugibabafod/33781128290.pdfIn PDF document text
    • https://s3.amazonaws.com/fuzafuzeruwit/wotesafonakofovij.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/eb75cca6-4be4-4d27-a276-ceb638bf5d6e/69769828851.pdfIn PDF document text
    • https://s3.amazonaws.com/ritoma/51883425140.pdfIn PDF document text
    • https://s3.amazonaws.com/tigovatolis/the_grape_cure_book.pdfIn PDF document text
    • 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
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_004_off00014d01.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x14D01 29996 bytes
SHA-256: 1149d886d4954b3a72c52903cb14746172f7d92f69ed16776d6aec6753cd58f5
font_00_sfnt_off00011390.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11390 5684 bytes
SHA-256: 62f161e09fe993365d6cedd67b80f9431b551386fd19fe3773f128be89cf718a
font_01_sfnt_off000126e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x126E1 12452 bytes
SHA-256: dac0b10bf14bf08cb8e8e0548dbc7929c5ce88ca336dc81c4245f11359d44f0b