Malicious PDF — malware analysis report

Static analysis result for SHA-256 e21b1bf151002dee…

MALICIOUS

PDF

41.7 KB Created: 2020-08-25 03:11:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 255a0057ec62978719d9aa610b80d5e5 SHA-1: 64a03e7185f6a24ec16ee1f21e487a5869b746d6 SHA-256: e21b1bf151002dee76c67e68d757d9f20594733cdee6b9a46fbc6b8cb611066a
154 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, with a critical heuristic firing for a PDF link to known malicious redirector infrastructure. The document body, though heavily obfuscated, contains the URL that triggered the redirector heuristic. The ML classifier also strongly indicated maliciousness. The primary attack pattern observed is a link farm designed to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • 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.
  • 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/pify?keyword=personification+worksheet+4
    • http://files.wotta.co.uk/uploads/1/3/1/6/131637136/pikunereti.pdf
    • http://files.plearnmc.com/uploads/1/3/0/7/130775306/munagon_pivuganul.pdf
    • http://files.almsandfare.com/uploads/1/3/2/7/132712093/dodesiguga.pdf
    • http://files.skardamaplefarms.com/uploads/1/3/2/6/132681836/5174281.pdf
    • http://ditivimid.bostonroundtable.org/uploads/1/3/1/4/131482992/nezigolija.pdf
    • https://cdn.shopify.com/s/files/1/0437/1818/1013/files/bootstrap_admin_template_with_vertical_menu.pdf
    • https://cdn.shopify.com/s/files/1/0434/3637/6231/files/57046651511.pdf
    • https://cdn.shopify.com/s/files/1/0435/2340/8032/files/82331719186.pdf
    • https://cdn.shopify.com/s/files/1/0433/9993/8211/files/rigivoguw.pdf
    • https://cdn.shopify.com/s/files/1/0430/3493/5447/files/wanerilurajofuge.pdf
    • https://cdn.shopify.com/s/files/1/0434/1766/5703/files/74581520423.pdf
    • https://cdn.shopify.com/s/files/1/0431/5866/7415/files/duzusu.pdf
    • https://cdn.shopify.com/s/files/1/0433/7414/9793/files/biotecnologia_industrial_livro.pdf
    • https://cdn.shopify.com/s/files/1/0439/3703/8494/files/git_cherry_pick.pdf
    • https://cdn.shopify.com/s/files/1/0438/2657/7570/files/gawepatulirasaw.pdf
    • 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/

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000058c2.bin
41dc8328298815faf941edd7f518849a1d4dacf3bd214acea7719c123f3e5f56
pdf-font-stream PDF embedded font (sfnt) at offset 0x58C2 4968 bytes
font_01_sfnt_off000069a6.bin
5f4e51400ffef7b669efff8fc2792cfdf9bbd4b79e6766ca041ba9a2c4eca970
pdf-font-stream PDF embedded font (sfnt) at offset 0x69A6 10060 bytes
font_02_sfnt_off00008bfe.bin
a542ec26cea93e049a2e27cd59b1347dd9bbdea13775fd7b822b3c2b3136116f
pdf-font-stream PDF embedded font (sfnt) at offset 0x8BFE 4324 bytes