Malicious PDF — malware analysis report

Static analysis result for SHA-256 d29f13ca46372686…

MALICIOUS

PDF

76.5 KB Created: 2021-03-14 08:20:51 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 0f0892c23fb120182315e3795a89ea8e SHA-1: c4cbe96be846536470a9d7450f99ca720d1e843d SHA-256: d29f13ca463726865ae3b593e38cf4989d4052a1dc324e43e9700723fea1a752
126 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many of which point to disposable hosting services, indicating a link farm or SEO spam campaign. The document body text, though partially corrupted, suggests a lure related to PDF modification. The ML classifier strongly flagged this PDF as malicious, and the presence of embedded URLs further supports a malicious intent to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 5

  • 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://gimoguvi.ru/award?keyword=apporter+des+modifications+sur+un+pdf PDF link annotation
    • http://rumigipasi.iblogger.org/curso_aprendizajes_clave_primaria_contestado.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379477/normal_601f94ff8f4ca.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4393189/normal_5fec0f7244f35.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4490264/normal_601cce355a6d2.pdfIn PDF document text
    • https://satufimitu.weebly.com/uploads/1/3/4/7/134715308/9aa469464514b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4412890/normal_6018dd44929ce.pdfIn PDF document text
    • https://jubipolofolexi.weebly.com/uploads/1/3/2/3/132302872/fuseraxomifadavegita.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4421959/normal_603effbbba5d3.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4390661/normal_602b67f94f2ae.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4393016/normal_5fe38441265ae.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4459926/normal_5fca917c3c93a.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4412891/normal_5fe0a834273c4.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4378164/normal_5fc7ff5a3d813.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/kuxuxemu/nudakutalusurew.pdfIn PDF document text
    • https://s3.amazonaws.com/zunaporam/spanish_alphabet_pronunciation_chart.pdfIn PDF document text
    • http://tizoraponu.rf.gd/niv_study_bible_large_print_online.pdfIn PDF document text
    • http://wuzuruwevirelu.rf.gd/warc_web_archive_file_format.pdfIn PDF document text
    • https://s3.amazonaws.com/zebarufuridorur/vebape.pdfIn PDF document text
    • https://s3.amazonaws.com/farowug/54744787892.pdfIn PDF document text
    • https://s3.amazonaws.com/lezopobigeza/what_are_the_best_dog_clippers_for_home_use_uk.pdfIn PDF document text
    • https://s3.amazonaws.com/dabatisew/alcatel_one_touch_manual_espaol.pdfIn PDF document text
    • https://s3.amazonaws.com/resabomibogodaw/77285892988.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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000eac1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAC1 5260 bytes
SHA-256: 64cc47ea21fccc6a60c93560971f8bc36378deb6db989a20d63d1d9867045026
font_01_sfnt_off0000fc91.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC91 13176 bytes
SHA-256: d6759d122d15b85335b50fdef2eb0fd960e69fe87eb5c7275fcd84d96ed3f981