Malicious PDF — malware analysis report

Static analysis result for SHA-256 53a7ffecab6808cf…

MALICIOUS

PDF

40.9 KB Created: 2020-07-19 18:44:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-09-24
MD5: 511ea5cce12ae28038455ec026cc0ac7 SHA-1: e86d38ef6276ecca9b1a9b0528a326222aa98281 SHA-256: 53a7ffecab6808cf9cb48d5be83a26deb3a43246eb125ca59a734994e01ee901
194 Risk Score

Malware Insights

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

The PDF document employs a lure of free architectural house plans to entice users. It contains a significant number of embedded links, identified as a link farm, pointing to external PDF files. One of these links directs to a known malicious redirector infrastructure, increasing the likelihood of malicious intent. No scripts were extracted, and the document body was heavily obfuscated.

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.com/wb?keyword=free%20architectural%20house%20plans%20pdf In PDF document text
    • http://files.dvbpaintings.com/uploads/1/3/0/9/130969192/getafukixene_bisisabufekolut_xelapamirabofi.pdfIn PDF document text
    • http://files.jpvahelloworld.com/uploads/1/3/0/7/130739971/21252ef18e.pdfIn PDF document text
    • http://files.bmldi.com/uploads/1/3/0/8/130873914/6453867.pdfIn PDF document text
    • http://files.rockfishdesigns.com/uploads/1/3/1/4/131483143/f6536d19.pdfIn PDF document text
    • http://files.gangneungtours.com/uploads/1/3/1/8/131857117/677169.pdfIn PDF document text
    • http://files.entirebeing.com/uploads/1/3/1/3/131398219/6033821.pdfIn PDF document text
    • http://files.lowbros.us/uploads/1/3/1/6/131607733/ab51e1fb.pdfIn PDF document text
    • http://files.gkellerguitars.com/uploads/1/3/1/4/131453618/xozojosumimat-poxunukawa-jirumeladot-tafuxuve.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://rezuloj.files.wordpress.com/2020/07/wuwenizatofepuzipikep.pdfIn PDF document text
    • https://guwasuxumoz.files.wordpress.com/2020/07/21453387845.pdfIn PDF document text
    • https://pulonoxone.files.wordpress.com/2020/07/tamalojufowugesutitosar.pdfIn PDF document text
    • https://fowetekiger.files.wordpress.com/2020/06/gokeveriruruf.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/1975/4907/files/19772764018.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0427/8072/1311/files/jodofiriwuwafozaxuxarutex.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/davunaxejapezuxipuwuwozom.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0434/1340/5850/files/29969348308.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/5408/8871/files/96026267528.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0431/6495/8879/files/90135498144.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0430/1576/6177/files/93820305835.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0430/1009/7313/files/91069333400.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_off00006201.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x6201 5080 bytes
SHA-256: f5137e3395b5ee733c3d89cd041604016b9e3dafdb4838c437060050e037d3dc
font_01_sfnt_off00007339.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x7339 10244 bytes
SHA-256: 1a80363cbcbe162dae0659366c8a078e8c5955cabefa02b467b5285416df319a