Malicious PDF — malware analysis report

Static analysis result for SHA-256 1d1cdca7f43b215a…

MALICIOUS

PDF

43.1 KB Created: 2020-09-01 02:54:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e8dbb884c600de03e66d31959a487d05 SHA-1: c90602a1f6c31339cb4abfa24ac7857a4421fe1a SHA-256: 1d1cdca7f43b215a21138229ffb6d3f7d349ad6b96d2ff7555dc3407e93ff397
154 Risk Score

Malware Insights

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

The PDF contains a critical heuristic firing for a malicious redirector link, pointing to 'https://ttraff.cc/wix?keyword=assinatura+com+certificado+digital+em+pdf'. This URL is presented within the document body, disguised as a link for confirming a digital signature. The document also exhibits characteristics of a link farm, with numerous embedded URLs, many pointing to Shopify domains, likely for obfuscation or to appear legitimate. 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.cc/wix?keyword=assinatura+com+certificado+digital+em+pdf
    • https://static.usrfiles.com/ugd/8ab72e_14e2dbd868d044d386b9d3450c6fe039.pdf
    • https://static.usrfiles.com/ugd/e3c460_451b9e8880df428e96383f4defb6e306.pdf
    • https://static.usrfiles.com/ugd/b8c837_bdc6f285362147cfa31e5fbd468489fa.pdf
    • https://cdn.shopify.com/s/files/1/0430/8900/2645/files/nosafexopadodofatubewef.pdf
    • https://cdn.shopify.com/s/files/1/0427/8134/3903/files/79084307334.pdf
    • https://cdn.shopify.com/s/files/1/0432/9209/8716/files/48265208188.pdf
    • https://cdn.shopify.com/s/files/1/0436/9098/3574/files/33075035802.pdf
    • https://cdn.shopify.com/s/files/1/0438/2782/2752/files/patrones_de_corte_y_confeccion.pdf
    • https://cdn.shopify.com/s/files/1/0431/3789/2509/files/52414648796.pdf
    • https://cdn.shopify.com/s/files/1/0433/8139/1514/files/google_analytics_mobile_reporting.pdf
    • https://cdn.shopify.com/s/files/1/0427/7737/8972/files/teribuxiside.pdf
    • https://cdn.shopify.com/s/files/1/0435/7786/8443/files/17697434796.pdf
    • https://cdn.shopify.com/s/files/1/0430/7573/1616/files/83239321484.pdf
    • https://static.usrfiles.com/ugd/ca300b_b3e46623fe5c435d86a78748062b0a87.pdf
    • https://static.usrfiles.com/ugd/f3ecbe_911937d9336041a89ed5240ef8879043.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_off00006a2a.bin
f8696ffde5637b06fe306a6299142d367248978a4beb9aaa9c680a932f5a60a1
pdf-font-stream PDF embedded font (sfnt) at offset 0x6A2A 5464 bytes
font_01_sfnt_off00007cac.bin
30f8291f6e28cf2f0c46122746462c2d37005bcbbdaf68a7b7ee8621a0a3e6c5
pdf-font-stream PDF embedded font (sfnt) at offset 0x7CAC 10072 bytes