Malicious PDF — malware analysis report

Static analysis result for SHA-256 df1a44cdd7e1795c…

MALICIOUS

PDF

42.3 KB Created: 2020-08-30 20:47:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f4a91b621a83c96432ba219060752763 SHA-1: 13dbe3a7616098d018e43a28fdaf26737ba4aba8 SHA-256: df1a44cdd7e1795c66fb1ad006cf2844fb522893edbb23671eface62bba3cdd3
152 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded links, a common technique for SEO poisoning or redirecting users to malicious sites. One of the embedded URLs, 'https://ttraff.ru/wix?keyword=tricky+test+2+make+3+cubes', is flagged as a malicious redirector. The ML classifier also strongly indicated maliciousness. No scripts were extracted, and the document body was heavily obfuscated, but the link farm and malicious redirector are strong indicators of a phishing or content-luring attack.

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=tricky+test+2+make+3+cubes
    • https://cdn.shopify.com/s/files/1/0434/7743/4525/files/print_booklet_to_indesign.pdf
    • https://cdn.shopify.com/s/files/1/0430/9785/0010/files/23382415772.pdf
    • https://cdn.shopify.com/s/files/1/0431/8999/3636/files/zulamotireraxuxukowon.pdf
    • https://static.usrfiles.com/ugd/b8c837_60fce5d3d096494685c0eb07b89e421d.pdf
    • https://static.usrfiles.com/ugd/b8c837_0a6e6c3af0e04fbc8a3a456fb6f199ea.pdf
    • https://static.usrfiles.com/ugd/2ac701_6aad7c6b16754df39661ca8f21af97d3.pdf
    • https://static.usrfiles.com/ugd/b8c837_410ac11a24bc4a97b1c6fbf94b111d5f.pdf
    • https://static.usrfiles.com/ugd/05900a_ed63adfacf0d40ff8d45a7e4c69a56c9.pdf
    • https://static.usrfiles.com/ugd/0049ca_a4ef2b9972554baca815fc9f270be44c.pdf
    • https://static.usrfiles.com/ugd/d99ef3_2a39fc93cd5a4f739612df6356744876.pdf
    • https://static.usrfiles.com/ugd/b8c837_404531e346b44571b85ab469ac98a2ca.pdf
    • https://static.usrfiles.com/ugd/b8c837_c692caf4a0a64d8ca1ba09c60602eacc.pdf
    • https://static.usrfiles.com/ugd/b8c837_8085a27cd85f49db829fb5347bfbe09d.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_off000064f2.bin
36c09f575998ae7c437d215fd8f06eafaa084c23b735b238cc46130e41a16ec7
pdf-font-stream PDF embedded font (sfnt) at offset 0x64F2 5464 bytes
font_01_sfnt_off00007775.bin
555953fb25b65fa95a5f38b1a339b8b9a043ef3cc71ed0248b11162b7a0358c1
pdf-font-stream PDF embedded font (sfnt) at offset 0x7775 10656 bytes