Malicious PDF — malware analysis report

Static analysis result for SHA-256 fa58fd06685176d0…

MALICIOUS

PDF

40.7 KB Created: 2020-08-14 12:38:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f6d778e78f2721f042cd2e3ea7115d50 SHA-1: 8be405dcbb3f41a0b6c4f6887f8c206d4d231b1a SHA-256: fa58fd06685176d02ca7c91c7741af70c12f79708e2a8ff3279b5b038f4763c1
152 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many of which point to suspicious domains. The heuristic PDF_MALICIOUS_REDIRECTOR_LINK specifically identifies a link to ttraff.ru, a known malicious redirector. The ML classifier also strongly indicated maliciousness. The document body, though heavily obfuscated, contains the URL https://ttraff.ru/wb?keyword=improvisation%20its%20nature%20and%20practice%20in%20music%20pdf, confirming its role as a redirector.

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/wb?keyword=improvisation%20its%20nature%20and%20practice%20in%20music%20pdf
    • http://pivufapaw.eastbrooklynbid.com/uploads/1/3/1/3/131381679/puwonitivofofoj-dufibof-repakobigewopu-kotat.pdf
    • http://wewojo.nymica.com/uploads/1/3/2/6/132682883/lubaxatab.pdf
    • http://zaturob.shrinedads.com/uploads/1/3/1/4/131406717/vazatasulu.pdf
    • http://files.michellehepburn.org/uploads/1/3/0/7/130739385/vixelaxul.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/78394199391.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/texirid.pdf
    • https://cdn.shopify.com/s/files/1/0430/6305/0394/files/cadsofttools_to_dwg_free.pdf
    • https://cdn.shopify.com/s/files/1/0434/8814/9654/files/87641629469.pdf
    • https://cdn.shopify.com/s/files/1/0441/4255/9384/files/sazolotiwijapilinamere.pdf
    • https://cdn.shopify.com/s/files/1/0433/2834/0123/files/38562512691.pdf
    • https://cdn.shopify.com/s/files/1/0434/3182/1473/files/dukomuxadejudavuziju.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/rojifibopi.pdf
    • https://cdn.shopify.com/s/files/1/0450/7769/2581/files/como_ser_calculista.pdf
    • https://cdn.shopify.com/s/files/1/0437/9272/8226/files/52874915104.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_off000062b2.bin
26d906f84df27b827b375103003bb7bf4ad8e96a85f9a4dd823fa212cfb59759
pdf-font-stream PDF embedded font (sfnt) at offset 0x62B2 5264 bytes
font_01_sfnt_off00007481.bin
ad80ea434f0a9338aa82eb148c6334a089571bd768e7a56e395227e90036efa8
pdf-font-stream PDF embedded font (sfnt) at offset 0x7481 9724 bytes