Malicious PDF — malware analysis report

Static analysis result for SHA-256 41b1f081bf8ea972…

MALICIOUS

PDF

36.5 KB Created: 2020-08-31 07:47:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 0a43d3f9f9342ccbe5139e0120290476 SHA-1: 330898426e0f9071d924ad60f6e685d35af54e22 SHA-256: 41b1f081bf8ea97292af3366cbdcc2465c2150e611cc1a2c5c82a8f997382b52
152 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious Link

The PDF contains a critical heuristic firing for a malicious redirector link, pointing to ttraff.ru. The document body, though heavily obfuscated, contains the URL 'https://ttraff.ru/wix?keyword=asus+ac55+driver', suggesting a lure related to driver downloads. The presence of numerous other PDF links, many hosted on static.usrfiles.com, indicates a link farm strategy. The ML classifier also 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.ru/wix?keyword=asus+ac55+driver
    • https://static.usrfiles.com/ugd/95089d_588e89a243744deb848898463963d525.pdf
    • https://static.usrfiles.com/ugd/b8c837_abcc28a4d8af49968202b82dd3743905.pdf
    • https://static.usrfiles.com/ugd/eaf48f_14a20ba1d04d4a06af16bd4fa2bd41c1.pdf
    • https://static.usrfiles.com/ugd/e2f197_79b56abb7b6f4f06a4e5386c5315f1c7.pdf
    • https://static.usrfiles.com/ugd/de60da_01ce585c1cab4fd89cf2d0773a33941f.pdf
    • https://static.usrfiles.com/ugd/b8c837_14d5b98d8a524ed79a238b69e8ec879b.pdf
    • https://static.usrfiles.com/ugd/21e6f2_1c398bd27a314da1ab048b924eb22e2f.pdf
    • https://static.usrfiles.com/ugd/b8c837_fba881b756674e429f852991f1cceaf2.pdf
    • https://static.usrfiles.com/ugd/b8c837_8d6882410fd848d0a33e1b415cfd021a.pdf
    • https://static.usrfiles.com/ugd/d4a9d6_93af821a4dcf4db9beaa67a5ef1efcc5.pdf
    • https://static.usrfiles.com/ugd/b8c837_40f16f11a69a442181997954451dbc2f.pdf
    • https://static.usrfiles.com/ugd/6c032c_3195c8c3195d43d1be98d525b897b343.pdf
    • https://static.usrfiles.com/ugd/b8c837_f48536f7208c499baacd5fd2431ace0c.pdf
    • https://static.usrfiles.com/ugd/4b68be_f426c0cea2e146c3862ae5770e64f461.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000045d9.bin
afe3d5c530145bec70c0fc92e11e2d8c5a6a85c88c7b3b38938039c5497ad5c3
pdf-font-stream PDF embedded font (sfnt) at offset 0x45D9 4660 bytes
font_01_sfnt_off000055bd.bin
a487fbcae3c2cf666a31a96cf46d428d49b4519cf269920441d9efa49be21906
pdf-font-stream PDF embedded font (sfnt) at offset 0x55BD 10000 bytes
font_02_sfnt_off00007779.bin
9f355172d696dda274cac500966718f112ce76951f19577ac4888987ea6471b2
pdf-font-stream PDF embedded font (sfnt) at offset 0x7779 4324 bytes