Malicious PDF — malware analysis report

Static analysis result for SHA-256 a71649d297145645…

MALICIOUS

PDF

49.2 KB Created: 2020-08-31 20:38:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 05500f989284ebe422e1373e7e04a1cb SHA-1: 0191f99cfd4e82def89621ce53838d1f9436b58b SHA-256: a71649d297145645438ed4f900eced42710cb499fba32aac2926b03b1f3815c4
150 Risk Score

Malware Insights

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

The PDF contains a critical heuristic firing for a malicious redirector link, specifically pointing to 'https://ttraff.ru/wix?keyword=netacad+cisco+chapter+10+answers'. This URL is embedded within the document body, which appears to be a lure for study material. The presence of a large number of external PDF links, many hosted on 'static.usrfiles.com', further indicates a link farm or SEO poisoning attempt to drive traffic to malicious sites. The ML classifier also strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 3

  • 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.
  • 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=netacad+cisco+chapter+10+answers
    • https://static.usrfiles.com/ugd/61f964_23cb424922174e00861acc1973b39c3c.pdf
    • https://static.usrfiles.com/ugd/b8c837_2897f64348bb49408520d58ad836a485.pdf
    • https://static.usrfiles.com/ugd/48f461_7354a78ec3f748c9b73904593e7e8d08.pdf
    • https://static.usrfiles.com/ugd/b8c837_3ef50415c0cc45869f8709e6938f417d.pdf
    • https://static.usrfiles.com/ugd/3f80ec_ca9d715da91e4d5f8f2d174618c57e81.pdf
    • https://static.usrfiles.com/ugd/63022f_6a02bd1835ff4b4282def99fef2bd4c6.pdf
    • https://static.usrfiles.com/ugd/a59130_14ee818c38fd4bbaba251944e0e5c90e.pdf
    • https://static.usrfiles.com/ugd/b8c837_733be6816e294ab59cf03ba9757d797e.pdf
    • https://static.usrfiles.com/ugd/fd3290_7e305fc217584f7dac8051e7d8b4b07a.pdf
    • https://static.usrfiles.com/ugd/12f4eb_f907bc00439e4f8d821af4a5e9f7e148.pdf
    • https://static.usrfiles.com/ugd/2f3ac6_dea5c91d37614c67987814880e44a1cd.pdf
    • https://static.usrfiles.com/ugd/3d0627_08386c2a186d420295c8dc2596751f0a.pdf
    • https://static.usrfiles.com/ugd/b8c837_1c47477d0a47479489360f4e2d25dbbc.pdf
    • https://static.usrfiles.com/ugd/822ecd_4c898a901b474dcc9dbdc20ad1fe90d9.pdf
    • https://static.usrfiles.com/ugd/d54300_a1c4da5827cb44c19d773d95405cfbd7.pdf
    • https://static.usrfiles.com/ugd/b8c837_ff99d61fcb7346d69b9b03948866c7bd.pdf
    • https://static.usrfiles.com/ugd/ab922d_809301c9ac534b908da8070e0e712e62.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_off0000757f.bin
9f91a24221545b37176b93ba8dc8cf3d2eaff1ae5d0bbcec5e84addfecbfdd19
pdf-font-stream PDF embedded font (sfnt) at offset 0x757F 5172 bytes
font_01_sfnt_off0000871b.bin
9197d7cc8bf60204650427b6054266231161dd9ead0154440cf85dc3e8e4b3af
pdf-font-stream PDF embedded font (sfnt) at offset 0x871B 10204 bytes
font_02_sfnt_off0000a9d9.bin
9f355172d696dda274cac500966718f112ce76951f19577ac4888987ea6471b2
pdf-font-stream PDF embedded font (sfnt) at offset 0xA9D9 4324 bytes