Malicious PDF — malware analysis report

Static analysis result for SHA-256 4b28b321bfa418cc…

MALICIOUS

PDF

80.8 KB Created: 2020-08-31 07:49:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f21eeab50126581a6a0642ec0d051ac7 SHA-1: aaf9d751e44ba2b5ab474b40bd8a050a47e4c9ee SHA-256: 4b28b321bfa418ccce92aa5b3107df938f44b50e16521c5d804c615affc39284
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell

The PDF file contains a large number of embedded links, a technique often used to create link farms for SEO manipulation or to distribute malicious content. One of the primary links points to a known malicious redirector. The ML classifier also strongly indicated maliciousness. No scripts were extracted, but the presence of a malicious redirector URL is a high-confidence indicator of malicious intent.

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.com/wix?keyword=sandra+cisneros+name
    • https://static.usrfiles.c
    • https://cdn.shopify.com/s/files/1/0431/3609/0267/files/kusezusitilaxexu.pdf
    • https://cdn.shopify.com/s/files/1/0434/8503/6706/files/bodosonosu.pdf
    • https://cdn.shopify.com/s/files/1/0438/2290/7549/files/dslr_camera_pro_apk_free.pdf
    • https://cdn.shopify.com/s/files/1/0437/4642/7031/files/algae_culture_medium.pdf
    • https://cdn.shopify.com/s/files/1/0431/5129/4619/files/46490954783.pdf
    • https://static.usrfiles.com/ugd/097bd5_00090b6449ae4baf9e80056766a23c21.pdf
    • https://static.usrfiles.com/ugd/b8c837_c7d37e80d8e0448bb75a25450414a129.pdf
    • https://static.usrfiles.com/ugd/52b593_af68e6dd703e4fef8af00e289f408520.pdf
    • https://static.usrfiles.com/ugd/74c34a_f28a1d7c7e8e42638847379d6aaf9b24.pdf
    • https://static.usrfiles.com/ugd/b8c837_a3fd9b5e9e7149e3a74771c19502f741.pdf
    • https://static.usrfiles.com/ugd/822ecd_fc3cb230ba65458a9c3c22190469b1c8.pdf
    • https://static.usrfiles.com/ugd/b8c837_db9f3a9a24f44c1f9b25eea88cc6337d.pdf
    • https://static.usrfiles.com/ugd/edb4a7_a86d6b0ca77e46849bc8e7dbe58061ad.pdf
    • https://static.usrfiles.com/ugd/b8c837_4ad506e16d354203ab18ad88794e9d11.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_off0000f720.bin
51789059eedc9dded1ca989ba6a9d7cc716ff24b2ec496fbbbfaec41f6378dcc
pdf-font-stream PDF embedded font (sfnt) at offset 0xF720 5156 bytes
font_01_sfnt_off0001087f.bin
381a57fef4563268e09c2a4c5733f9e217f101cd7feeaed5077cab44874f981c
pdf-font-stream PDF embedded font (sfnt) at offset 0x1087F 14860 bytes