Malicious PDF — malware analysis report

Static analysis result for SHA-256 88d22f1823f095d9…

MALICIOUS

PDF

40.7 KB Created: 2020-09-01 01:39:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d78d945e6b55d7aa635d9b817dd38ff3 SHA-1: 739b7b0b553c48c093b920ae20afe2965d7bce05 SHA-256: 88d22f1823f095d97a2d40fef1a1ea280b79b0df4329f4b015ca0a46a49a7d69
152 Risk Score

Malware Insights

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

The PDF file was identified as malicious by an ML classifier and contains a significant number of embedded links, characteristic of a link farm. One of these links, 'https://ttraff.ru/wix?keyword=bowman+lake+ca+fishing+report', redirects to known malicious infrastructure. The document body appears to be obfuscated or corrupted, but the presence of numerous links and the malicious redirector strongly suggest an attempt to lure users to malicious sites, likely for SEO poisoning or to distribute further malware.

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=bowman+lake+ca+fishing+report
    • https://static.usrfiles.com/ugd/784815_4f668d5a328a4e979a9b59976bfb5972.pdf
    • https://static.usrfiles.com/ugd/902d29_123bfa2951d24a219bc0fc1f04de676c.pdf
    • https://static.usrfiles.com/ugd/83f04e_55589ce7ac23429faa70044759814eb3.pdf
    • https://static.usrfiles.com/ugd/b8c837_84bbaa6a675a47808ba7cc0227446871.pdf
    • https://static.usrfiles.com/ugd/b8c837_5e0003f6df384570a96f39d9c6e2e33e.pdf
    • https://static.usrfiles.com/ugd/15ebe2_6429eab3245f44ada0b676136b4fed48.pdf
    • https://static.usrfiles.com/ugd/bfbc46_d29a8f157fda470ca2283b23095d30ee.pdf
    • https://static.usrfiles.com/ugd/df4650_c9404a161aec48b0b6574a54a3e8178d.pdf
    • https://static.usrfiles.com/ugd/b8c837_32f6563762d24f5e9b8764a9afd3a3ee.pdf
    • https://static.usrfiles.com/ugd/df4650_d0ca8978990e484ebaa361a148ab9c8f.pdf
    • https://static.usrfiles.com/ugd/61b8bf_0a49e7db4c9f412cbb094a8a762b20da.pdf
    • https://static.usrfiles.com/ugd/7598fa_05ed0540ac004400b2a18b546f5a9ebf.pdf
    • https://static.usrfiles.com/ugd/9b5f63_94da5959aa7a497ba0fba259ba64f930.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_off00005ff6.bin
3aec966d2bcbd9a09126e3585aa51cc7c2e430a80127982b40ff1bbbca5ad45e
pdf-font-stream PDF embedded font (sfnt) at offset 0x5FF6 5636 bytes
font_01_sfnt_off0000730c.bin
c6c0ba1a39bcdc17e7703bbf47916b6e7cbaeae9ba901fc55da43485be894649
pdf-font-stream PDF embedded font (sfnt) at offset 0x730C 10680 bytes