Malicious PDF — malware analysis report

Static analysis result for SHA-256 71cffa5b931b3074…

MALICIOUS

PDF

62.5 KB Created: 2020-08-30 17:58:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: aa1e9901dce17e77057c3b83223ffe04 SHA-1: 6d7ba9e5a61b8d9e8f6a7c91ec7778ab3650a92c SHA-256: 71cffa5b931b307483994c3a9451a4b5bc0c09d721a10866b771c2e8cc74ac07
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file contains a large number of embedded links, many of which point to a malicious redirector URL. The primary purpose appears to be SEO link farming, directing traffic through the malicious URL. The ML classifier strongly indicated maliciousness, and the presence of a known malicious redirector confirms this. No scripts were extracted, but the embedded links are sufficient evidence of malicious intent.

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.com/wix?keyword=etica+cristiana+medieval
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0434/5076/1377/files/76926764951.pdf
    • https://cdn.shopify.com/s/files/1/0433/9879/1329/files/98540913327.pdf
    • https://cdn.shopify.com/s/files/1/0431/1135/0439/files/kisasaxapajimasagupibid.pdf
    • https://cdn.shopify.com/s/files/1/0434/4732/0728/files/bodemoferi.pdf
    • https://cdn.shopify.com/s/files/1/0428/8030/3267/files/nopirubovi.pdf
    • https://static.usrfiles.com/ugd/b8c837_373e51d2c003456db1c69914a14cc01c.pdf
    • https://static.usrfiles.com/ugd/de60da_31d3250ed3fd4eddab77cc2b08fe7de2.pdf
    • https://static.usrfiles.com/ugd/b8c837_e457ef8d9ca54f368d538eec07eb97c9.pdf
    • https://static.usrfiles.com/ugd/f459ea_bd60cd1626a94a24b4a732d7e908f20c.pdf
    • https://static.usrfiles.com/ugd/0bcf16_c6b6651aa7924c978bc37a4617638c1f.pdf
    • https://static.usrfiles.com/ugd/c1108c_166a6cb1f10b4210b405897cfdc233e5.pdf
    • https://static.usrfiles.com/ugd/b8c837_08eeb43d05254791a498f9333ada8f1e.pdf
    • https://cdn.shopify.com/s/files/1/0431/4375/7992/files/lawujaradufodugu.pdf
    • https://cdn.shopify.com/s/files/1/0435/3848/1320/files/diplomacy_trait_pathfinder.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_off0000b557.bin
f3ba6c70fcab2c17d27a4a8c3270226cf193a244ca91dcd331ff7baadd2fd358
pdf-font-stream PDF embedded font (sfnt) at offset 0xB557 5104 bytes
font_01_sfnt_off0000c697.bin
a061cf79c9c034594278b1dddee74714ba8f9fe871b9db62b6d880dec522c63f
pdf-font-stream PDF embedded font (sfnt) at offset 0xC697 11912 bytes