Malicious PDF — malware analysis report

Static analysis result for SHA-256 2d85bbae363fab4a…

MALICIOUS

PDF

33.3 KB Created: 2020-08-31 03:25:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 273b078ba810a234f9ef606aad8d12b2 SHA-1: 661e0102ee5b8a03b49843a6bf949be9c6e78946 SHA-256: 2d85bbae363fab4aac9be2d92726857516fbf00fbf5209318ff1b48378728bc6
154 Risk Score

Malware Insights

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

The PDF contains a critical heuristic firing for a malicious redirector link, pointing to 'https://ttraff.ru/wix?keyword=descarga+de+mp3+tubidy'. Additionally, it exhibits characteristics of a PDF SEO link farm, with numerous links to external PDFs, including one hosted on 'static.usrfiles.com'. The document body, though partially corrupted, contains the same redirector URL, reinforcing the malicious intent. The ML classifier also strongly indicated maliciousness.

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=descarga+de+mp3+tubidy
    • https://static.usrfiles.com/ugd/b8c837_758a16ec0518498996994908b41602d4.pdf
    • https://static.usrfiles.com/ugd/a4e402_47cf652164424b4c80a8ea9cfe115ccc.pdf
    • https://static.usrfiles.com/ugd/23b571_fa92e0995663460a9722993485e4912b.pdf
    • https://static.usrfiles.com/ugd/b8c837_b6d52c594b6346f6a852138a574443f8.pdf
    • https://static.usrfiles.com/ugd/b8c837_e41db60785a940b79d36a42069d4c010.pdf
    • https://static.usrfiles.com/ugd/f09a9d_15bd7d4ca8f4425692a05d51b0ab4f55.pdf
    • https://static.usrfiles.com/ugd/2e4eb4_632518bb14884f5dbaec35579fa6789a.pdf
    • https://static.usrfiles.com/ugd/493135_082f6eafe486446494221e22ca2a9bab.pdf
    • https://static.usrfiles.com/ugd/b6bf5b_b6a9fcba1f2542b094d7110985a2d8d5.pdf
    • https://static.usrfiles.com/ugd/b8c837_200bcc54443142c6971b52fa5d04d81c.pdf
    • https://static.usrfiles.com/ugd/764aaa_afb59d9b92034a1c9f13ad614bc929d9.pdf
    • https://static.usrfiles.com/ugd/b8c837_1b4078be1ad94920a9a9c9a07c1541c3.pdf
    • https://cdn.shopify.com/s/files/1/0430/9729/2967/files/kutasifinanol.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/xakikalimakimoxe.pdf
    • https://cdn.shopify.com/s/files/1/0429/5376/9123/files/99330138604.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_off00004481.bin
b68b792d690fe6b4c240aa7f11dd15e540bc20cd6059755e1875ee86eafa78be
pdf-font-stream PDF embedded font (sfnt) at offset 0x4481 5764 bytes
font_01_sfnt_off0000580d.bin
b2e417b35135a558d7e4aa6ef135d42c1936fa4c1403919473626e5ca1b5f6e0
pdf-font-stream PDF embedded font (sfnt) at offset 0x580D 9600 bytes