Malicious PDF — malware analysis report

Static analysis result for SHA-256 b2b5ed69d3524754…

MALICIOUS

PDF

55.5 KB Created: 2020-08-29 22:40:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1be5ccba53f23be8cc7d9c3f2e40fb06 SHA-1: ccc9c01741e8bf99483c1b5e829bd4710a3fd591 SHA-256: b2b5ed69d35247548dfc48c6305a4ffd31e4cfca72f03a39e5dc979fd1312305
152 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, with a critical heuristic firing indicating it redirects to known malicious infrastructure. The document body, though heavily obfuscated, contains the primary malicious URL and references to other benign-looking PDF files, suggesting a link farm or redirection scheme. 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=bootstrap+4+cheat+sheet+download
    • https://static.usrfiles.com/ugd/1a89c8_c59df947283246bb817708ec11f9cbcc.pdf
    • https://static.usrfiles.com/ugd/b8c837_0d7f62b6f81141dda8cfe8bf027d8c86.pdf
    • https://static.usrfiles.com/ugd/162fe6_78e7f7d43bea4e29a61c6faa6ac0d143.pdf
    • https://cdn.shopify.com/s/files/1/0432/9573/5976/files/58248168543.pdf
    • https://cdn.shopify.com/s/files/1/0432/2462/9411/files/dositojewugiborozob.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/1568204463.pdf
    • https://cdn.shopify.com/s/files/1/0436/1453/5843/files/dead_cells_trainer.pdf
    • https://cdn.shopify.com/s/files/1/0430/7025/9357/files/35008415285.pdf
    • https://cdn.shopify.com/s/files/1/0434/4968/0028/files/fulafogixivinebovabamej.pdf
    • https://cdn.shopify.com/s/files/1/0437/0006/0310/files/60140378105.pdf
    • https://static.usrfiles.com/ugd/b8c837_f51a4045a515473d84f23bf42b5d6aa6.pdf
    • https://static.usrfiles.com/ugd/b5472a_3aa8c9f5d2914d7d8fc6aeea1858ae4a.pdf
    • https://static.usrfiles.com/ugd/b8c837_35d3db8336d54936aa31c4e28ce2f8f0.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_off00009c19.bin
34d58d5f56c378fa7262ee4f87e4dd92e5c57a317005958b9413602ad4f2fea9
pdf-font-stream PDF embedded font (sfnt) at offset 0x9C19 5392 bytes
font_01_sfnt_off0000ae7c.bin
b548484cabf3de7d4e525a68d5bb2f808ea2a2851572d316c73880797269d597
pdf-font-stream PDF embedded font (sfnt) at offset 0xAE7C 10244 bytes