Malicious PDF — malware analysis report

Static analysis result for SHA-256 bda3ddefbc2b9010…

MALICIOUS

PDF

39.9 KB Created: 2020-09-10 01:02:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 3086df974a6d57a1ea8ca9a78fdcaf55 SHA-1: 344e0f16b93a41fc1b1574bdc718539711f5fd46 SHA-256: bda3ddefbc2b9010240476398869dc6b506be79ce71a1e5cd3821cc088509b3c
152 Risk Score

Malware Insights

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

The PDF file was flagged as malicious due to the presence of a redirector link pointing to 'https://ttraff.club/pify?keyword=nct+u+boss'. Additionally, the file contains a large number of external PDF links, many of which are hosted on 'static.usrfiles.com', suggesting a link farm or SEO poisoning attempt. The ML classifier strongly supports the malicious verdict. No scripts were extracted, and the document body was largely unreadable, but the presence of the malicious redirector is sufficient evidence for a malicious classification.

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.club/pify?keyword=nct+u+boss
    • http://pevir.kristalynnhughes.com/uploads/1/3/2/6/132681579/fa24e8bc.pdf
    • http://files.seanstrees.com/uploads/1/3/1/4/131482975/rumaf-kufigawusabeka-vuziro.pdf
    • http://files.pageantdoll.com/uploads/1/3/0/8/130813458/xizovuwu.pdf
    • http://tusagi.ro2art.com/uploads/1/3/1/0/131070786/pesogaziz.pdf
    • http://files.enotecaathena.com/uploads/1/3/1/3/131383949/tuxefalibiwamo-nezopivotawu.pdf
    • http://files.womaninchair.com/uploads/1/3/2/8/132815298/5574171.pdf
    • https://static.usrfiles.com/ugd/96564c_d27b30b89c9a4ce5a45849024ec73895.pdf
    • https://static.usrfiles.com/ugd/3f4b99_17c56a249fc34905872cda41d20b0c24.pdf
    • https://static.usrfiles.com/ugd/277b62_67a854884c0b4d2f81ede8f0f13997a7.pdf
    • https://static.usrfiles.com/ugd/930050_8ae58309913b4437aec847ec30e3e10a.pdf
    • https://static.usrfiles.com/ugd/3e87bf_a2f1e0659228406d8bcc53406be98b20.pdf
    • https://static.usrfiles.com/ugd/d32f78_362154eed152437a8fa9aac9e5033315.pdf
    • https://static.usrfiles.com/ugd/c79b1c_9cf2edd032be47fbbc81a81dc58dad84.pdf
    • https://static.usrfiles.com/ugd/7f614e_0be494a6368642d398b0e5763f4d09e3.pdf
    • https://static.usrfiles.com/ugd/40512e_296656354f5c4a1f84a97027026151fc.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_off00006304.bin
97ddae121a0fb7b1bc1042542c59e7aff1ad73924fb76123936d66f6efb5206f
pdf-font-stream PDF embedded font (sfnt) at offset 0x6304 4564 bytes
font_01_sfnt_off000072a6.bin
e89174b79c3d55a8c23a1686b46a4f9fe07f7727c8f1306527d43ec1fab9a6ff
pdf-font-stream PDF embedded font (sfnt) at offset 0x72A6 9556 bytes