Malicious PDF — malware analysis report

Static analysis result for SHA-256 638b77b6876a29d2…

MALICIOUS

PDF

39.3 KB Created: 2020-09-02 15:36:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 74d6db17001ddfdbebcd0d6ce74a05d5 SHA-1: 6efd56fed2babacbd04753352edde9e9839672a8 SHA-256: 638b77b6876a29d27e86d09d413b8783786b457bdbbf3ad6a473a466ab9e24be
154 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many of which point to external resources, indicating a link farm or SEO manipulation tactic. One critical heuristic identified a link to known malicious redirector infrastructure, suggesting a phishing or malware distribution attempt. The document body, though partially corrupted, contains a title related to electrical diagrams, likely used as a lure.

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.link/wix?keyword=circuit+diagram+of+auto+transformer+starter
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0440/0916/0862/files/repizorivosawiwanepigugot.pdf
    • https://cdn.shopify.com/s/files/1/0437/9662/7618/files/australasian_animal_registry_forms.pdf
    • https://cdn.shopify.com/s/files/1/0429/6730/2295/files/vufakiwonegadanexifuru.pdf
    • https://cdn.shopify.com/s/files/1/0429/4272/6310/files/59936897859.pdf
    • https://cdn.shopify.com/s/files/1/0433/7205/2643/files/15868150495.pdf
    • https://cdn.shopify.com/s/files/1/0432/3885/0719/files/43996878017.pdf
    • https://cdn.shopify.com/s/files/1/0435/3651/5221/files/strategic_management_concepts.pdf
    • https://cdn.shopify.com/s/files/1/0432/6578/6006/files/38304462590.pdf
    • https://cdn.shopify.com/s/files/1/0440/3937/2965/files/pitilufenukezexer.pdf
    • https://static.usrfiles.com/ugd/516574_31c46cfd5e484f6aa90508ad061ad972.pdf
    • https://static.usrfiles.com/ugd/d17951_722b4a3acd284f5a85346149b50c117e.pdf
    • https://static.usrfiles.com/ugd/b8c837_818fe1d25b1149c4bd0ae8845076063f.pdf
    • https://static.usrfiles.com/ugd/b8c837_12809f604e8b41ebbcd610dc5a19006f.pdf
    • https://static.usrfiles.com/ugd/b48b60_cdf4f51d7e60461da37bb5bebea58a01.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_off00005bf3.bin
1af4184aa90804a2138687f131ab792a6f5ac078107b8da824fc5adc511b1a77
pdf-font-stream PDF embedded font (sfnt) at offset 0x5BF3 5212 bytes
font_01_sfnt_off00006d97.bin
2630f76a36844f7a9cd141527715c41cf478f310e0e1831bea824a89c5e00054
pdf-font-stream PDF embedded font (sfnt) at offset 0x6D97 10140 bytes