Malicious PDF — malware analysis report

Static analysis result for SHA-256 5a8fb3bb208ab5d6…

MALICIOUS

PDF

48.6 KB Created: 2020-08-30 13:50:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e955bac1dc05aa0e4b4f189a85c324a6 SHA-1: f04d8d3ca3668f6a4be053b3efc2dfbc2c6de857 SHA-256: 5a8fb3bb208ab5d6b0e75a2ea2894af532648a9a1afbe283a3f6df1e27162c53
162 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains embedded links that redirect to malicious infrastructure, specifically identified by the 'PDF_MALICIOUS_REDIRECTOR_LINK' heuristic. The document body, though heavily obfuscated, suggests a lure related to 'free business credit application form pdf'. The presence of a large number of external PDF links also indicates a link farm, likely for SEO manipulation or to host further malicious content. The ML classifier strongly flagged this PDF as malicious.

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.
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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/wix?keyword=free+business+credit+application+form+pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://static.usrfiles.com/ugd/19103d_0d0b2f3f70904fa48a25a542a682f1bd.pdf
    • https://static.usrfiles.com/ugd/d162e3_b60a695f6c5a4e669ab43518d1033331.pdf
    • https://static.usrfiles.com/ugd/d55797_a214dbfaa8784753b82fe1cfc24e11d3.pdf
    • https://static.usrfiles.com/ugd/b8c837_6ff7f1d9d89e4e2789087cad1ca41012.pdf
    • https://static.usrfiles.com/ugd/b8c837_ad74b0de7d444d92bd1906a93270d4a2.pdf
    • https://cdn.shopify.com/s/files/1/0433/2702/9400/files/vidmate_for_iphone_uptodown.pdf
    • https://cdn.shopify.com/s/files/1/0431/8127/7352/files/amazing_facts_about_earth.pdf
    • https://cdn.shopify.com/s/files/1/0437/6304/0408/files/minority_scholarship_verification_form.pdf
    • https://cdn.shopify.com/s/files/1/0435/6544/9371/files/65807357629.pdf
    • https://cdn.shopify.com/s/files/1/0437/2935/4917/files/18187799553.pdf
    • https://static.usrfiles.com/ugd/b8c837_d7be3290c59e42d39fbaece658f1d0a6.pdf
    • https://static.usrfiles.com/ugd/6240f8_d6306b40df344b20ae130182e966a9da.pdf
    • https://cdn.shopify.com/s/files/1/0433/9689/0785/files/1746465780.pdf
    • https://cdn.shopify.com/s/files/1/0434/0314/9462/files/72207633611.pdf
    • https://cdn.shopify.com/s/files/1/0429/3158/5180/files/best_free_tv_apps_for_android_uk.pdf
    • https://cdn.shopify.com/s/files/1/0435/5588/1119/files/oxford_bookworms_library_stage_6_free.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00007239.bin
e793f7e415872959bbc54101ff424345a5354c2699f0c002657ace0dff840657
pdf-font-stream PDF embedded font (sfnt) at offset 0x7239 5276 bytes
font_01_sfnt_off00008402.bin
4e96c444d2ef9466b08dd401d09670edcaac17af06423c7ea13c9caf895f1239
pdf-font-stream PDF embedded font (sfnt) at offset 0x8402 10224 bytes
font_02_sfnt_off0000a6e1.bin
4fcfa7c68d76e23b667942a3ac892d2d5d88346478daafc61479ad4df4af3dd3
pdf-font-stream PDF embedded font (sfnt) at offset 0xA6E1 4324 bytes