Malicious PDF — malware analysis report

Static analysis result for SHA-256 f5738353b10c538f…

MALICIOUS

PDF

32.1 KB Created: 2020-09-05 13:04:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 36938b25c123d56393c3c23c8f7d1217 SHA-1: 0ac096d256e5a1aeb3eae73bf4583aff5a2c71c3 SHA-256: f5738353b10c538f5d28f268b2e82069ea8b6dae50eecedd4851fdd3f40f6ec3
152 Risk Score

Malware Insights

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

The PDF contains a link farm designed to mimic search results for educational materials, specifically 'slader spanish 3 textbook answers'. The primary malicious URL, https://ttraff.me/wix?keyword=slader+spanish+3+textbook+answers, is a known redirector. The document body, though heavily obfuscated, contains references to this lure and numerous other benign-looking PDF links, likely to obscure the malicious intent. The ML classifier strongly supports the malicious verdict.

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.me/wix?keyword=slader+spanish+3+textbook+answers
    • https://static.usrfiles.com/ugd/de3d83_d53a3dd2318d4987bb9c7a82e3b033d1.pdf
    • https://static.usrfiles.com/ugd/7ea8bb_5d75775dab0640ee8f6c73681c193fc1.pdf
    • https://static.usrfiles.com/ugd/0ad6c7_4a2fcb8542d74b078578c71b49d18587.pdf
    • https://static.usrfiles.com/ugd/735189_cc9610b9e4a143fd8a36d21c9520b310.pdf
    • https://static.usrfiles.com/ugd/0e6328_a80ab87bc07c457684ddc44487b04876.pdf
    • https://static.usrfiles.com/ugd/d1d005_6f785ac89e5840edbe61b8720d7d6335.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/xidegafizupewutuzu.pdf
    • https://cdn.shopify.com/s/files/1/0434/4948/3420/files/54634360107.pdf
    • https://cdn.shopify.com/s/files/1/0434/5269/4680/files/bfa_herbalism_leveling_guide.pdf
    • https://static.usrfiles.com/ugd/5b9365_b18e0a7223f248d0b1b378fe6c2cd81f.pdf
    • https://static.usrfiles.com/ugd/a838c0_6a4028fde93445d9ac67a99190b4a2aa.pdf
    • https://static.usrfiles.com/ugd/d162e3_2300717fc2d4489c9e10f48b9e94b86c.pdf
    • https://static.usrfiles.com/ugd/7d21c0_0988c1b4fb704290b45c6d78adbaae7e.pdf
    • https://static.usrfiles.com/ugd/1715bf_ef462d518b3844b69cfa968eca327f4d.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_off000042a5.bin
9b81b4387183a6f218eb5cf3beac9e61b46e1835d1ad340302a95c719ef1cea9
pdf-font-stream PDF embedded font (sfnt) at offset 0x42A5 5680 bytes
font_01_sfnt_off00005600.bin
8bd8d2dcd970bb331694c0f3672dd8b84a15dac21b8975e3f60725b51ee48d37
pdf-font-stream PDF embedded font (sfnt) at offset 0x5600 8696 bytes