Malicious PDF — malware analysis report

Static analysis result for SHA-256 879fbb5ff855d50e…

MALICIOUS

PDF

45.1 KB Created: 2020-08-09 03:01:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: ebc9d6ff15b560bb997d1987da1d1029 SHA-1: 12e26f6ca29d4998f886a34583ab49ec0d7dcbd9 SHA-256: 879fbb5ff855d50e6752e1368e2c5f7fdafd57fbb70ee630bbfcacaf5ab17017
154 Risk Score

Malware Insights

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

The PDF contains a critical heuristic firing for a malicious redirector link, pointing to 'https://ttraff.ru/pify?keyword=complex+carbohydrates+list+for+diabetics+pdf'. The document body, though partially corrupted, also contains this URL and appears to be a lure related to diabetic diets. The presence of a large number of external PDF links, many hosted on Shopify, suggests a link farm or SEO poisoning tactic to distribute the 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.ru/pify?keyword=complex+carbohydrates+list+for+diabetics+pdf
    • http://files.spiritfire.com/uploads/1/3/1/1/131164574/nipugewozizexej_lojifoji.pdf
    • http://files.webfirethemes.com/uploads/1/3/1/4/131453869/d9c14596622a8.pdf
    • http://files.travismulhauser.com/uploads/1/3/1/3/131381640/xikar-wojukerepas.pdf
    • http://files.multiairfreight.com/uploads/1/3/1/8/131856283/a985a475896.pdf
    • https://cdn.shopify.com/s/files/1/0429/8683/2035/files/xijalu.pdf
    • https://cdn.shopify.com/s/files/1/0434/5033/5384/files/algorithms_illuminated_part_2_graph_algorithms_and_data_structures.pdf
    • https://cdn.shopify.com/s/files/1/0429/5042/6780/files/43247931256.pdf
    • https://cdn.shopify.com/s/files/1/0431/9258/2293/files/carnegie_learning_integrated_math_2.pdf
    • https://cdn.shopify.com/s/files/1/0435/4736/1439/files/hackerrank_problems_and_solutions.pdf
    • https://cdn.shopify.com/s/files/1/0429/9931/6639/files/95012893828.pdf
    • https://cdn.shopify.com/s/files/1/0433/9934/8389/files/kabudixi.pdf
    • https://cdn.shopify.com/s/files/1/0430/5318/7223/files/voseteripo.pdf
    • https://cdn.shopify.com/s/files/1/0434/7317/4680/files/pijigar.pdf
    • https://cdn.shopify.com/s/files/1/0429/9217/3217/files/33058014048.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_off00006a7b.bin
c71e97bce8f214d1dd0a6228c3eaa2e605be49d7b7a5805561f099d1aa03d25d
pdf-font-stream PDF embedded font (sfnt) at offset 0x6A7B 5612 bytes
font_01_sfnt_off00007d61.bin
6ba396ad8c37f8161675a058387241e9bda2da1983204e9d87a37106def8a3fc
pdf-font-stream PDF embedded font (sfnt) at offset 0x7D61 13320 bytes