Malicious PDF — malware analysis report

Static analysis result for SHA-256 1638861a624ed11b…

MALICIOUS

PDF

51.4 KB Created: 2020-04-25 04:22:49 +03:00 Authoring application: wkhtmltopdf 0.12.1.4 (via Qt 4.8.6)
MD5: 01a2f0e3604578db71369da68d6ec865 SHA-1: f5ddff9b677a6b3fe57bfb5194f2098fe83da7f9 SHA-256: 1638861a624ed11b90756fe376a985e148a352742f5db01db26758e726ab31fd
136 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which appear to be part of a link farm designed to obscure malicious content. The heuristic 'SE_PASSWORD_ARCHIVE_LURE' indicates the document likely instructs the user to decrypt an archive, a common tactic to bypass security filters. The ML classifier strongly flagged this PDF as malicious, supporting the conclusion that it is part of a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

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.
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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://adriannicolas.com/uploads/1/3/0/4/130436492/130436492.html#paraiso+travel+libro+pdf+completo
    • http://charterpathways.com/uploads/1/3/0/6/130604227/4540764.pdf
    • http://my-trg.com/uploads/1/3/0/6/130605509/jedasiwuneweped.pdf
    • http://theroyalpriesthoodblog.com/uploads/1/3/0/5/130542953/sitawalalajuvep.pdf
    • http://brasymmetry.com/uploads/1/3/0/6/130639461/wisogukemugugepajo.pdf
    • http://happygamesorg.com/uploads/1/3/0/6/130604152/5029850.pdf
    • http://kundalinico-op.com/uploads/1/3/0/6/130639038/4895a.pdf
    • http://afewupliftingwords.com/uploads/1/3/0/3/130379466/deropuzebulewitutuda.pdf
    • http://uscsa.org/uploads/1/3/0/5/130588493/1666759.pdf
    • http://steeleharbor.net/uploads/1/3/1/1/131163917/zebezuvamotutiluki.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • 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/
    • https://fedoraproject.org/wiki/Licensing/LiberationFontLicense
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00007c42.bin
6661ffae9d8733fe4bf3ce5b40db90c40082439a419ef05bcfdd3dc75ef5e633
pdf-font-stream PDF embedded font (sfnt) at offset 0x7C42 10276 bytes
font_01_sfnt_off0000a104.bin
e91619dfd4c72a85464d95ef1ba4e67df13020651c42071bafbe521a61d9f7fc
pdf-font-stream PDF embedded font (sfnt) at offset 0xA104 2652 bytes
font_02_sfnt_off0000aa6b.bin
779aa567746046747dac965df7fdfb06ff632674a0a99ce247a327bf89f0fa63
pdf-font-stream PDF embedded font (sfnt) at offset 0xAA6B 16036 bytes