Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c27c80ab7051497…

MALICIOUS

PDF

39.2 KB Created: 2020-08-19 07:10:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 24ffebe85c00a3de16bc62ca35b27e4e SHA-1: b7df6e386577722660b6b830009adf01da37c881 SHA-256: 8c27c80ab7051497b63b671684799a450164d549fb3d05a5ba01dd69169bed8a
154 Risk Score

Malware Insights

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

The PDF contains a mass of external links, including one to a known malicious redirector at ttraff.cc. The document body, though heavily obfuscated, appears to contain the URL for the redirector and several other URLs hosted on cdn.shopify.com, likely as part of a link farm to improve SEO for malicious content. The ML classifier also strongly indicated maliciousness.

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.cc/pify?keyword=comparing+fractions+worksheet+grade+5
    • http://files.mrfirme.org/uploads/1/3/0/7/130776609/7428100.pdf
    • https://cdn.shopify.com/s/files/1/0436/8610/1145/files/jipekofilozazo.pdf
    • https://cdn.shopify.com/s/files/1/0434/4204/5090/files/a_an_the_kullanm.pdf
    • https://cdn.shopify.com/s/files/1/0433/3250/1656/files/goradufuvofodejevogunel.pdf
    • https://cdn.shopify.com/s/files/1/0431/5817/5906/files/taxuvamefawobonigabikobi.pdf
    • https://cdn.shopify.com/s/files/1/0447/3988/7255/files/akcent_video_songs_free_mp4.pdf
    • https://cdn.shopify.com/s/files/1/0431/1033/4620/files/calabozos_y_dragones_juego_android.pdf
    • https://cdn.shopify.com/s/files/1/0437/6068/1111/files/3406b_injection_pump_exploded_view.pdf
    • https://cdn.shopify.com/s/files/1/0448/5585/3218/files/22468307892.pdf
    • https://cdn.shopify.com/s/files/1/0427/8845/4559/files/resigomikosisuregag.pdf
    • https://cdn.shopify.com/s/files/1/0430/9437/6599/files/cyclone_tracy_movie.pdf
    • https://cdn.shopify.com/s/files/1/0435/8651/9203/files/mulevalijekedisitufusepu.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_off00005a05.bin
aabdb15d5ab5fde71b1124321275045f2a1a326767ed2e5f7282f66e4f8d7b67
pdf-font-stream PDF embedded font (sfnt) at offset 0x5A05 5724 bytes
font_01_sfnt_off00006d60.bin
c0a5c84f3e35bec9cfba2b169d69dffc77fc62f7e4870959450142afa207315f
pdf-font-stream PDF embedded font (sfnt) at offset 0x6D60 10120 bytes