Malicious PDF — malware analysis report

Static analysis result for SHA-256 474b270387074ae9…

MALICIOUS

PDF

76.7 KB Created: 2021-02-13 11:13:33 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: c5acb0a21ce7610edc1f1c4b09e0d451 SHA-1: 443f920a623e0d4b16462b60fdd6b087ab44dd0b SHA-256: 474b270387074ae9c4f19ad6a55f6a941071f45240f7d1c0dab9cf4c8c93ea7b
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ClamAV and an ML classifier, with heuristics indicating it functions as a link farm. It contains numerous external URIs, including one pointing to 'bologen.ru', suggesting a phishing or malware distribution attempt. The document body, though heavily obfuscated, contains metadata related to 'wkhtmltopdf', indicating its likely generation method for SEO spam.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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.
  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://bologen.ru/wix?keyword=red+flag+warning+meaning
    • https://cdn-cms.f-static.net/uploads/4472484/normal_5fd8d4ca7c14f.pdf
    • https://menudobuwowewil.weebly.com/uploads/1/3/4/7/134765252/4fb67b.pdf
    • https://cdn-cms.f-static.net/uploads/4494432/normal_601b1bab567b1.pdf
    • https://wekimede.weebly.com/uploads/1/3/4/8/134862148/3547587.pdf
    • http://obschee.xyz/25673588860hog99.pdf
    • https://static.s123-cdn-static.com/uploads/4493282/normal_5fdf9cd44e916.pdf
    • https://rezigetofetima.weebly.com/uploads/1/3/1/1/131163738/1361879.pdf
    • https://niwarixetawozav.weebly.com/uploads/1/3/4/1/134108921/pomareku.pdf
    • https://static.s123-cdn-static.com/uploads/4368997/normal_5ff07b0db4b10.pdf
    • http://agentsecure.space/fuzufupagovegujalosikuxhrmq.pdf
    • https://rebijigubewu.weebly.com/uploads/1/3/4/7/134770847/tadofawimudalaje.pdf
    • http://esmoney.site/vomuswlwh9.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/bopuxosavubare/55226268895.pdf
    • https://s3.amazonaws.com/zazelujeju/free_printable_2019_yearly_calendar_template.pdf
    • https://s3.amazonaws.com/pevuwarobuvowa/cartoon_network_anything_she_apk.pdf
    • https://s3.amazonaws.com/nimuwet/edhesive_quiz_2_answers.pdf
    • https://s3.amazonaws.com/boxujetanonikuv/28623677741.pdf
    • https://s3.amazonaws.com/xulepiwa/adobe_acrobat_professional_editor_free.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f12c.bin
e5fcca7037a8ff8b72ffbdf3969da32d9deeb9a6450c8cafac4a735498881e2c
pdf-font-stream PDF embedded font (sfnt) at offset 0xF12C 5148 bytes
font_01_sfnt_off000102b4.bin
d11c41aebe8e695887106debb1c93722ebdd49d86140d1632452b7c5d0896dc4
pdf-font-stream PDF embedded font (sfnt) at offset 0x102B4 10148 bytes