Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d77342fd58d4b86…

MALICIOUS

PDF

51.5 KB Created: 2020-04-04 06:27:17 +03:00 Authoring application: wkhtmltopdf 0.12.1.4 (via Qt 4.8.6) First seen: 2020-08-25
MD5: bf3e4e08cf3f84e2b8041b1c0078e252 SHA-1: 0d8e56a976f74dfaccefe29d1bb37efbe7dc4696 SHA-256: 8d77342fd58d4b8685491ca6f01f95bb10959678f830573ef566716dd9b88b55
96 Risk Score

Malware Insights

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

The PDF file contains a large number of external links to other PDF documents hosted on various domains. This behavior is indicative of a link farm or a mechanism to distribute further malicious content. The ML classifier strongly flagged this PDF as malicious, supporting the assessment of a malicious intent. No scripts were extracted, and the document body is largely unreadable binary data, making it difficult to determine the exact payload or purpose beyond link distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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://peacefulfarewell.com/uploads/1/3/0/8/130873965/130873965.html#precision+exactitud+y+resolucion+de+un+instrumento+de+medicion PDF link annotation
    • http://def-mbl.org/uploads/1/3/0/2/130270874/bebojuseja.pdfIn PDF document text
    • http://garlysboutique.com/uploads/1/3/1/0/131071298/339781.pdfIn PDF document text
    • http://galaxychocolates16.com/uploads/1/3/0/4/130475994/e1e6dc2.pdfIn PDF document text
    • http://wcbbbs.org/uploads/1/3/0/7/130775589/114cbc9.pdfIn PDF document text
    • http://nwalife.org/uploads/1/3/1/4/131437566/fofewozususamo.pdfIn PDF document text
    • http://staffingspecialistaz.com/uploads/1/3/0/4/130435531/122861aaa80a4ff.pdfIn PDF document text
    • http://glassworx.info/uploads/1/3/0/5/130539287/c2cc5.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: cartcootiecovers.com 4 samples

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00007ba5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x7BA5 10044 bytes
SHA-256: aed64c97238054a6b605a1616f19e473fbf29bb4205538badf4931de83f0de97
font_01_sfnt_off00009efc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x9EFC 2964 bytes
SHA-256: 6aea181b4ca5e1e7a9e814e0a0cda763fae6c820df400ef7f7abdd358d959726
font_02_sfnt_off0000a921.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xA921 16036 bytes
SHA-256: 779aa567746046747dac965df7fdfb06ff632674a0a99ce247a327bf89f0fa63