Malicious PDF — malware analysis report

Static analysis result for SHA-256 31945e2eb20cd0b9…

MALICIOUS

PDF

41.6 KB Created: 2020-08-31 21:06:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d2305f1281f3a4cca263081b127520c4 SHA-1: 29e9b919d1fe801fa3e0017ed9b0e315e5b9fe7b SHA-256: 31945e2eb20cd0b9fb9b13761420fe2e7ca83e05ccc3c21343de05e7cdf65622
152 Risk Score

Malware Insights

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

The PDF contains a link to a known malicious redirector, ttraff.com, which is disguised within content related to 'piano chords app for android free'. The PDF also hosts a large number of external links, many pointing to static.usrfiles.com, suggesting a link farm or SEO poisoning tactic to drive traffic to malicious sites. 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.com/wix?keyword=piano+chords+app+for+android+free
    • https://static.usrfiles.com/ugd/362633_bbe27b4ba87d4a6b82fab6053dc093e3.pdf
    • https://static.usrfiles.com/ugd/b8c837_d224297b83204df286bf3ea34a045d72.pdf
    • https://static.usrfiles.com/ugd/1df9ea_9f19ef001eaf48ba8d19295da91c93e3.pdf
    • https://static.usrfiles.com/ugd/0d089b_b8135c05edca4b8193919c315d55f7a6.pdf
    • https://static.usrfiles.com/ugd/88a84f_7214afa992314cf2b1d6191b7bf65c37.pdf
    • https://static.usrfiles.com/ugd/b8c837_b3d1e5b9c4dc424298829ba826c98630.pdf
    • https://static.usrfiles.com/ugd/565485_ce3389c254254e3086577f5cbb956e8a.pdf
    • https://static.usrfiles.com/ugd/a771bd_3d9ecafe8dc7420fb68bcdb8ab8cfd41.pdf
    • https://static.usrfiles.com/ugd/2ca09c_6daa07ef58be47d2a1431180ef1de286.pdf
    • https://static.usrfiles.com/ugd/b8c837_d9e7c9bed2094387a6a135083fc17d9a.pdf
    • https://static.usrfiles.com/ugd/bf650e_3dccfd46ec28425aa69e80409cb2013a.pdf
    • https://static.usrfiles.com/ugd/b8c837_e30834b7bebc4605ad908d10f6433425.pdf
    • https://static.usrfiles.com/ugd/b8c837_0abbcbbff42644c4a10cc8ae1872525a.pdf
    • https://static.usrfiles.com/ugd/c0b427_4aece5a0e586452283253129146756e1.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_off00006553.bin
c3ee062090a14cf83bc833f2f896ec2389be9ef5aab3c354878f5bd7b43de271
pdf-font-stream PDF embedded font (sfnt) at offset 0x6553 5212 bytes
font_01_sfnt_off0000770a.bin
7fdfd0951a19b6e9d5628f98d4b55bbd8038589642e6f4af9b40d1b0cc03ee3a
pdf-font-stream PDF embedded font (sfnt) at offset 0x770A 10132 bytes