Malicious PDF — malware analysis report

Static analysis result for SHA-256 adf9ed0901ae9f37…

MALICIOUS

PDF

56.6 KB Created: 2020-04-04 14:10:51 +03:00 Authoring application: wkhtmltopdf 0.12.1.4 (via Qt 4.8.6) First seen: 2020-09-24
MD5: af7b8ca4fff83888f1477b8b71ebcffc SHA-1: 5b07a99927321d987ac66aa00dcc990853c2bf65 SHA-256: adf9ed0901ae9f376f647bcbef29224d71583e9c4cb7251a61308bca21493f21
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of external links, many of which point to similarly structured URLs on different domains. This pattern is indicative of a link farm or SEO abuse tactic. The primary heuristic 'PDF_SEO_LINK_FARM' strongly suggests this, and the ML classifier also flagged it as malicious. The document body text, though heavily obfuscated, contains references to ASCII and binary tables, and the authoring application is wkhtmltopdf, suggesting it was programmatically generated to host these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

Heuristics 4

  • 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.
  • 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://suncitysnack.com/uploads/1/3/0/9/130968958/130968958.html#tabla+ascii+binario+completa PDF link annotation
    • http://bestmassagemobilemedical.org/uploads/1/3/0/2/130289209/348d709f24.pdfIn PDF document text
    • http://betterideautah.com/uploads/1/3/0/9/130969842/xegepa_nuwagaxesebu_tugowarodelesu_juvudal.pdfIn PDF document text
    • http://wolfecityreunion.com/uploads/1/3/0/4/130488412/5910666.pdfIn PDF document text
    • http://stylingcantaluppi.com/uploads/1/3/0/6/130604780/tetanoxabotof.pdfIn PDF document text
    • http://civilwarlady.org/uploads/1/3/1/4/131438025/betaroxov-saxuvoredeg-rabowinad.pdfIn PDF document text
    • http://helgajoseps.com/uploads/1/3/0/7/130739975/pifolotizusen.pdfIn PDF document text
    • http://tylerbradleyresume.com/uploads/1/3/0/7/130775590/0e123d95f.pdfIn PDF document text
    • http://alkioutfitters.com/uploads/1/3/0/6/130620602/622d6e50f3f.pdfIn PDF document text
    • http://windfallpartners.net/uploads/1/3/0/5/130544009/622813.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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
    • https://fedoraproject.org/wiki/Licensing/LiberationFontLicenseIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text
🗂 Part of campaign: get-solutions.net 5 samples

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00006ec1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x6EC1 22836 bytes
SHA-256: 26592967d250860f661682f5c944590af3106334c3769dc75400549c1d09b4ac
font_01_sfnt_off0000af2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF2D 6548 bytes
SHA-256: a0804e0a238ef16e7bc4510f7c1abd685ebf4558fad4b558cf3a441a1ad22fd9
font_02_sfnt_off0000bedc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBEDC 16036 bytes
SHA-256: 779aa567746046747dac965df7fdfb06ff632674a0a99ce247a327bf89f0fa63