Malicious PDF — malware analysis report

Static analysis result for SHA-256 f64089d23e6ecdc1…

MALICIOUS

PDF

82.1 KB Created: 2020-04-17 00:56:01 +03:00 Authoring application: wkhtmltopdf 0.12.1.4 (via Qt 4.8.6) First seen: 2020-09-24
MD5: 524df0b37946bbf8d1e7802d9f8b0cb9 SHA-1: 9d92de7223ec8165edd955bfb34e5be497f7b6de SHA-256: f64089d23e6ecdc17d13f0e31b27dcadfc2f2f2d87d9b75bb681a3d361a61711
104 Risk Score

Malware Insights

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

The PDF file contains a significant number of external links, many of which point to unrelated domains and appear to be part of a link farm. One heuristic specifically identified this as a 'PDF_SEO_LINK_FARM'. The document body, though partially garbled, contains a URL that is also listed as an IOC. This suggests the PDF is designed to host a large number of links, likely to improve search engine ranking for unrelated content while potentially leading users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9857

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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://gregjiel.com/uploads/1/3/1/0/131070207/131070207.html#chiari+malformation+type+one+symptoms PDF link annotation
    • http://zephyrhillfarmvt.com/uploads/1/3/1/4/131436978/7679440.pdfIn PDF document text
    • http://mahoneybodywork.com/uploads/1/3/0/7/130775825/lojuwuxona.pdfIn PDF document text
    • http://jakesweeneysweepers.com/uploads/1/3/0/6/130604090/690015f0a193c.pdfIn PDF document text
    • http://schurova.info/uploads/1/3/0/9/130969143/xidas-jubukolirojikew-jofutubi.pdfIn PDF document text
    • http://pufcorporation.com/uploads/1/3/0/7/130775674/1669435.pdfIn PDF document text
    • http://the-healthy-nerd.com/uploads/1/3/1/4/131406710/pizawo-nivisad-zoxalipikinup-vemenuwav.pdfIn PDF document text
    • http://abcnewsIn PDF document text
    • https://twitterIn 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000103e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103E5 9392 bytes
SHA-256: ab9b5b428fb28cf4d989c43e1a9d1139c51df93e41a4942233c32ade3ac63999
font_01_sfnt_off00012644.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12644 16232 bytes
SHA-256: 9b8376160d22215e4a89009b03154fd154ede5185c406f004ad21bc2564739da