Malicious PDF — malware analysis report

Static analysis result for SHA-256 71c19076f0c2f06b…

MALICIOUS

PDF

39.4 KB Created: 2020-08-25 12:04:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 77586a44752c69081ddcd4d5649878dd SHA-1: e326d00b90732bb6cf08fe5b530cad29885f0500 SHA-256: 71c19076f0c2f06bfefca751f8d3bb0252c99d375cd41e1e9cb23634fb585905
154 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many of which point to a redirector service known for malicious activity. The document body, though heavily obfuscated, contains a URL that appears to be a lure for educational content, likely to trick users into clicking the malicious links. The ML classifier also strongly indicated maliciousness.

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.com/pify?keyword=math+worksheets+for+middle+schoolers
    • http://files.stpatrickchurchyk.com/uploads/1/3/1/3/131381679/kepaxawajir.pdf
    • http://luzowizo.csnons.com/uploads/1/3/1/0/131070588/wopepidubukowas.pdf
    • http://wewazupa.crossfitkanga.com/uploads/1/3/2/6/132682883/14c4a2.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/46946939033.pdf
    • https://cdn.shopify.com/s/files/1/0428/5746/3964/files/clothes_accessories_worksheet.pdf
    • https://cdn.shopify.com/s/files/1/0431/7167/6314/files/cursive_writing_book_free_download.pdf
    • https://cdn.shopify.com/s/files/1/0435/3723/6117/files/36269099690.pdf
    • https://cdn.shopify.com/s/files/1/0437/0392/6952/files/99992100989.pdf
    • https://cdn.shopify.com/s/files/1/0446/7975/7977/files/72156501808.pdf
    • https://cdn.shopify.com/s/files/1/0432/3393/5515/files/the_secret_doctrine_helena_blavatsky.pdf
    • https://cdn.shopify.com/s/files/1/0434/5911/7206/files/87826557987.pdf
    • https://cdn.shopify.com/s/files/1/0431/2665/3090/files/needs_assessment_template_project_management.pdf
    • https://cdn.shopify.com/s/files/1/0428/9911/2095/files/9494476356.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/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005b57.bin
572b8a3dd719a0101c32ed4009a45042bfd1983accb2673bb94d09a6ac4ad023
pdf-font-stream PDF embedded font (sfnt) at offset 0x5B57 5420 bytes
font_01_sfnt_off00006dbc.bin
3649f955eddb19aa1a05b9a5e0f0a911dac19f87e2976b72dd0ec4637e1ce61a
pdf-font-stream PDF embedded font (sfnt) at offset 0x6DBC 10364 bytes