Malicious PDF — malware analysis report

Static analysis result for SHA-256 123f651c043fae8a…

MALICIOUS

PDF

55.8 KB Created: 2020-07-19 04:56:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-09-04
MD5: ef3438becf96f840ce9fc56296701a9f SHA-1: df036b983e5fea15f838ab9e008cf13668f5f281 SHA-256: 123f651c043fae8a941ca624d71895016e280e592adf7502ba4f7041ccc17096
194 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, many of which point to redirector infrastructure known for malicious activity. The heuristic firings indicate this PDF is a link farm designed to lure users into clicking on these links, likely leading to phishing sites or malware downloads. The ML classifier strongly supports the malicious nature of this document.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • 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://ttraff.ru/wb?keyword=web%20application%20security%20for%20dummies%20pdf In PDF document text
    • http://files.excelpowerusercourse.com/uploads/1/3/1/8/131856358/7518440.pdfIn PDF document text
    • http://files.gilliantorckler.com/uploads/1/3/0/8/130874629/gomenevidi-kinepowa-xasokipa-xupuzateseroji.pdfIn PDF document text
    • http://files.janettesdesignstudios.com/uploads/1/3/0/8/130874025/gokijibujov.pdfIn PDF document text
    • http://files.umicad.com/uploads/1/3/1/6/131637546/dujasesetoreda.pdfIn PDF document text
    • http://files.buiebeadz.com/uploads/1/3/0/8/130874647/1717715.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://xajezeduza.files.wordpress.com/2020/07/porirejewunuti.pdfIn PDF document text
    • https://duwarezozaju.files.wordpress.com/2020/07/mofosuvu.pdfIn PDF document text
    • https://busupigox846814838.files.wordpress.com/2020/07/51211007442.pdfIn PDF document text
    • https://nudokux.files.wordpress.com/2020/07/89097411384.pdfIn PDF document text
    • https://detofoxi222376319.files.wordpress.com/2020/07/62217523278.pdfIn PDF document text
    • https://navolag.files.wordpress.com/2020/07/95501405387.pdfIn PDF document text
    • https://fogojifoxuni.files.wordpress.com/2020/06/41679912256.pdfIn PDF document text
    • https://mawumobu.files.wordpress.com/2020/06/lusepa.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0432/9802/9733/files/33792308134.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0429/4865/7318/files/lifavavagisodefonulovexab.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0432/7899/1520/files/bujomugedixowarulavo.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0430/5669/3397/files/59150839753.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/3708/2271/files/66189425610.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0431/6849/7823/files/23098731206.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0432/1450/4093/files/dinir.pdfIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00009c28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x9C28 5440 bytes
SHA-256: f7189b5d7224b962e4842f02ba7468d0b4a5ecdf76e83b555705f6dea9ba5743
font_01_sfnt_off0000ae8e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAE8E 10240 bytes
SHA-256: e3aa4223031df3aa31f8c367a3e515f3f73693d75d009a85f70362875ff31da8