Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a76728ca030fd79…

MALICIOUS

PDF

72.2 KB Created: 2020-08-14 21:44:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e7b90fcd56d38945d808d4d67a26d042 SHA-1: 7af59c71762ad02a378fd6b418d072d808f3131a SHA-256: 4a76728ca030fd79563b668ed8a02aa82f58eff33e0923833f1d8c70bb8f0be9
154 Risk Score

Malware Insights

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

The PDF was flagged as malicious due to a critical heuristic identifying it as a redirector link to known malicious infrastructure. Additionally, it contains a PDF link farm, with many links pointing to Shopify domains hosting other PDFs. The primary malicious URL is https://ttraff.ru/pify?keyword=bts+butterfly+album, which is likely used to lure victims. The ML classifier also strongly indicated maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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=bts+butterfly+album
    • http://files.mostlymaille.com/uploads/1/3/2/6/132695867/pazidugifatutezexu.pdf
    • https://cdn.shopify.com/s/files/1/0431/0269/9681/files/mufasafiviv.pdf
    • https://cdn.shopify.com/s/files/1/0432/2299/1007/files/busukubaxuki.pdf
    • https://cdn.shopify.com/s/files/1/0432/6300/0734/files/xibiriretukiwunofamuna.pdf
    • https://cdn.shopify.com/s/files/1/0429/8833/9361/files/sbi_bank_exams_syllabus.pdf
    • https://cdn.shopify.com/s/files/1/0429/2041/1303/files/pilamurosepuwakubedu.pdf
    • https://cdn.shopify.com/s/files/1/0437/1139/8041/files/72543470843.pdf
    • https://cdn.shopify.com/s/files/1/0430/0383/8615/files/popular_pizza_toppings.pdf
    • https://cdn.shopify.com/s/files/1/0437/7201/8845/files/coldfusion_tutorial.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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00008787.bin
fdcb24932fa4ae43fb7388fc87437faa87cf0b81e7a747c9635ef98ccff8c787
pdf-font-stream PDF embedded font (sfnt) at offset 0x8787 21756 bytes
font_01_sfnt_off0000c9d4.bin
ed1521571f634ac6839e2d75708ce6df696520bbdff583b36794a0a0c8f5c998
pdf-font-stream PDF embedded font (sfnt) at offset 0xC9D4 4824 bytes
font_02_sfnt_off0000da3f.bin
d12d6b7ba6ad1d86cf8d4be04b16ed8fd9826554ff81b0c8c8563d5dd173145f
pdf-font-stream PDF embedded font (sfnt) at offset 0xDA3F 13876 bytes
font_03_sfnt_off00010640.bin
d1f4a20f0e35a0564be54678b929bb8c711862c507f070c2b9a6abea8daf4378
pdf-font-stream PDF embedded font (sfnt) at offset 0x10640 4324 bytes