Malicious PDF — malware analysis report

Static analysis result for SHA-256 bf678fdc8ef0e1c7…

MALICIOUS

PDF

44.8 KB Created: 2020-09-01 10:40:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 360b62fed0a32e870c4afbd65fe9bd2c SHA-1: 01b3f3b1701061392700868b2b717bf8aa916a24 SHA-256: bf678fdc8ef0e1c7dfa580bad735586b53cba673d945172a7929b1bedb9456e1
152 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, pointing to 'ttraff.cc'. The document body, though heavily obfuscated, contains the same URL and appears to be a lure related to 'wham last christmas piano sheet music pdf'. The presence of numerous other PDF links, many hosted on Shopify, suggests a link farm or SEO poisoning tactic to distribute the malicious URL. 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.cc/wix?keyword=wham+last+christmas+piano+sheet+music+pdf
    • https://cdn.shopify.com/s/files/1/0429/4829/6857/files/damuwopotugibos.pdf
    • https://cdn.shopify.com/s/files/1/0458/1448/1062/files/82321365314.pdf
    • https://cdn.shopify.com/s/files/1/0437/7667/1895/files/breeam_new_construction_2020.pdf
    • https://cdn.shopify.com/s/files/1/0429/3866/3079/files/weniwisewuja.pdf
    • https://static.usrfiles.com/ugd/9b33c5_241c109b12f1417099971d262e73b6b6.pdf
    • https://static.usrfiles.com/ugd/b8c837_c808b6b09c1e45648afa93b61cb4a8ea.pdf
    • https://static.usrfiles.com/ugd/affaa6_657e6cefa26645f2822ee42657072722.pdf
    • https://static.usrfiles.com/ugd/b8c837_73d44f7e83164624909aa3b40919c01f.pdf
    • https://static.usrfiles.com/ugd/98e298_74ebe7f161be41f384c58c463072ed24.pdf
    • https://static.usrfiles.com/ugd/c618e9_7b08ddc943b148fbb4b9e9093ffde7b1.pdf
    • https://static.usrfiles.com/ugd/b8c837_ed34aca71a40419b9ec8ee211011c7d6.pdf
    • https://static.usrfiles.com/ugd/b8c837_0b7fa430d1b84ce7bc63c90139dddeed.pdf
    • https://static.usrfiles.com/ugd/61f964_e0b94062010b44a1a29b38d9b67fd48a.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_off00006266.bin
be2cd6c27e2c2c2db9e4946f13843f55760164b4563191447dc213601ce70c6c
pdf-font-stream PDF embedded font (sfnt) at offset 0x6266 5408 bytes
font_01_sfnt_off000074ad.bin
f923a3dea05a87d65b727bfc8d2c74abafcf11f1d616096076f910325805e400
pdf-font-stream PDF embedded font (sfnt) at offset 0x74AD 15784 bytes