Malicious PDF — malware analysis report

Static analysis result for SHA-256 7dc5f70c81cca005…

MALICIOUS

PDF

36.5 KB Created: 2020-08-31 05:50:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: de5e306931869cb31505975c3b61c79c SHA-1: a75c4f3863cbcf2fc7a88fb0af3e8063e42f5811 SHA-256: 7dc5f70c81cca00511e6ab27682314c7295b3dfdd877eeb59b8a98e0bd2b5c4b
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell T1204.002 Malicious Link

The PDF file contains numerous embedded links, with a critical heuristic firing indicating a link to known malicious redirector infrastructure at `ttraff.ru`. The document body, though heavily obfuscated, appears to be a lure related to educational materials, specifically 'Apostila de alfabetização matematica pdf'. The presence of multiple Shopify links, while some are benign, suggests a link farm or SEO manipulation tactic to disguise the malicious intent. The ML classifier strongly flagged this PDF as malicious.

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/wix?keyword=apostila+de+alfabetiza%25C3%25A7%25C3%25A3o+matematica+pdf
    • https://cdn.shopify.com/s/files/1/0448/0129/4496/files/format_sd_card_canon.pdf
    • https://cdn.shopify.com/s/files/1/0430/6383/6834/files/android_sdk_tools_location_linux.pdf
    • https://cdn.shopify.com/s/files/1/0438/4240/4512/files/fannie_mae_guidelines_annuity_income.pdf
    • https://cdn.shopify.com/s/files/1/0440/8626/3960/files/27593084864.pdf
    • https://cdn.shopify.com/s/files/1/0435/7786/8443/files/ilpa_fee_reporting.pdf
    • https://static.usrfiles.com/ugd/9374a7_4894855d2f1f4c949483f82a25d5d467.pdf
    • https://cdn.shopify.com/s/files/1/0431/3638/5181/files/analytical_chemistry_notes_download.pdf
    • https://cdn.shopify.com/s/files/1/0440/0467/1646/files/digital_electronics_logic_gates.pdf
    • https://cdn.shopify.com/s/files/1/0434/1373/3534/files/veganismo_definicion.pdf
    • https://static.usrfiles.com/ugd/b8c837_157440d2edae43d6b7bdffdd7c5d561d.pdf
    • https://static.usrfiles.com/ugd/b8c837_779a8f071e7742d2b48e30c0235c4d51.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00004829.bin
70c6d3a5b12d092296992ba8552c91379443189b0c63708502a82a94e6ca95a2
pdf-font-stream PDF embedded font (sfnt) at offset 0x4829 5884 bytes
font_01_sfnt_off00005b3a.bin
cb56bcfca9cf8f22fb50511898c9cf1dad0b834ad28bcbfdf89a5a77fd8af2ff
pdf-font-stream PDF embedded font (sfnt) at offset 0x5B3A 13304 bytes