Malicious PDF — malware analysis report

Static analysis result for SHA-256 db5dbb86892a69e3…

MALICIOUS

PDF

46.1 KB Created: 2020-08-25 01:22:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f4c3133d45df90937ed8d0950ee51c8d SHA-1: 9e659d6ec8d05ba347f01db0b9e47d6e16a34e12 SHA-256: db5dbb86892a69e30608b5babbabdc776dfe7e4f6fedeea355dc4235a5bf71c8
152 Risk Score

Malware Insights

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

The PDF file contains a critical heuristic firing for linking to known malicious redirector infrastructure, specifically `https://ttraff.ru/pify?keyword=bangalore+central+university+time+table+2018+pdf`. Additionally, it exhibits characteristics of a PDF link farm, embedding numerous external links, some of which are hosted on potentially untrusted domains. The ML classifier also strongly indicated maliciousness. The document body, though heavily obfuscated, contains the aforementioned malicious URL and other URLs pointing to potentially hosted PDF files.

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/pify?keyword=bangalore+central+university+time+table+2018+pdf
    • http://files.lavendersweeprecords.com/uploads/1/3/1/1/131163492/0af22b54.pdf
    • http://files.casperstith.com/uploads/1/3/1/8/131856602/kuwozivi.pdf
    • http://files.pskehal.com/uploads/1/3/1/6/131606546/wugoridaxiwa.pdf
    • https://cdn.shopify.com/s/files/1/0429/7133/2767/files/how_to_change_minecraft_skin.pdf
    • https://cdn.shopify.com/s/files/1/0430/5489/1161/files/js_template_literals_multiline.pdf
    • https://cdn.shopify.com/s/files/1/0437/1637/8773/files/fafuzezes.pdf
    • https://cdn.shopify.com/s/files/1/0433/4823/0297/files/brass_in_pocket_chords.pdf
    • https://cdn.shopify.com/s/files/1/0429/9702/2871/files/nikeridadiviligi.pdf
    • https://cdn.shopify.com/s/files/1/0438/5007/2214/files/87587087973.pdf
    • https://cdn.shopify.com/s/files/1/0431/1787/1255/files/31613617315.pdf
    • https://cdn.shopify.com/s/files/1/0446/7176/2595/files/mp3_bangla_book_free_download.pdf
    • https://cdn.shopify.com/s/files/1/0436/3298/4222/files/wubaja.pdf
    • https://cdn.shopify.com/s/files/1/0436/7260/0726/files/how_to_factory_reset_nintendo_switch.pdf
    • https://cdn.shopify.com/s/files/1/0437/3846/4417/files/9569408519.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_off00007208.bin
fc92aaec6fe7170b3df171ccfa00e8cb9ec43996c0c7df86793dc99cb862389c
pdf-font-stream PDF embedded font (sfnt) at offset 0x7208 6344 bytes
font_01_sfnt_off00008795.bin
d46d7ef1c65a951b210421812a0e21ffdd943e8b0f5986159b3d1347dafd5c49
pdf-font-stream PDF embedded font (sfnt) at offset 0x8795 10416 bytes