Malicious PDF — malware analysis report

Static analysis result for SHA-256 137442c91812bd9d…

MALICIOUS

PDF

81.1 KB Created: 2020-08-30 16:14:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: fcc3b25c2ec2815dff6be0b6b2d52213 SHA-1: 363cabd42442343115917332ed5dca54289a3ead SHA-256: 137442c91812bd9dde594b5828bcca4e76204d7d35e56a24dc6aa9c84135b51b
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

The PDF contains a heuristic firing for PDF_MALICIOUS_REDIRECTOR_LINK, indicating a link to known malicious infrastructure. Additionally, PDF_SEO_LINK_FARM suggests the document is part of a link farm, with numerous external PDF links. The ML classifier also flagged this PDF with high confidence. The primary IOC is the malicious redirector URL, which is likely used to deliver a second-stage payload.

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=derrota+a+wiper+dentro+do+tempo+limi
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0431/0571/4338/files/62781699716.pdf
    • https://cdn.shopify.com/s/files/1/0433/9236/8798/files/jimavuk.pdf
    • https://cdn.shopify.com/s/files/1/0431/1570/8580/files/20075966738.pdf
    • https://static.usrfiles.com/ugd/b8c837_2e7d523d89d94073bf95834d739e8516.pdf
    • https://static.usrfiles.com/ugd/b8c837_de9313b406d64784937543534630954f.pdf
    • https://static.usrfiles.com/ugd/7dd30d_8a6fae9c9fa64f3499acaf0107579dda.pdf
    • https://static.usrfiles.com/ugd/585b1d_8681a107664a4124b5919a9cda14c9cf.pdf
    • https://static.usrfiles.com/ugd/30e015_3d3fa3bb9f75466393151e51bd0e40a2.pdf
    • https://static.usrfiles.com/ugd/32acb1_606b4ab789814dd2bbdf5236f2b8e732.pdf
    • https://static.usrfiles.com/ugd/b8c837_607e5fb06bcc44f8b07ec7d86fae0efb.pdf
    • https://static.usrfiles.com/ugd/b8c837_3544602e03e64af2b92d58f3b9961831.pdf
    • https://static.usrfiles.com/ugd/09273f_bfd7c9851ce9499a8d923f38d7ad8f2a.pdf
    • https://static.usrfiles.com/ugd/b8c837_0145bf18c102466d8f84fc9a9089e9d3.pdf
    • https://static.usrfiles.com/ugd/b8c837_a6ac94d7694e49bdafb1d80a59324829.pdf
    • https://static.usrfiles.com/ugd/3aca14_c660024636584d0f89e46475adfd4837.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/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010261.bin
0727e382a7e7ecafbd050375bd5da9cee13138060f1afa1a6adeb8320735008f
pdf-font-stream PDF embedded font (sfnt) at offset 0x10261 5016 bytes
font_01_sfnt_off0001136a.bin
b00830bcc35a25115ad20bd7fb42402f1f6d1a5b6724328f5e63fcfd204c0d44
pdf-font-stream PDF embedded font (sfnt) at offset 0x1136A 10392 bytes