Malicious PDF — malware analysis report

Static analysis result for SHA-256 a231f83072755b8d…

MALICIOUS

PDF

41.6 KB Created: 2020-08-09 20:06:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d5742009814f0483602988cef661a7f6 SHA-1: cec72598d49b4efa3d85eaa7fdde5549a9cf11c0 SHA-256: a231f83072755b8dc554c69c104eb297094741b12f3622001e57f801047759bb
152 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 'ttraff.com'. The document body, though heavily obfuscated, also contains this URL, suggesting it's the primary lure. The PDF also exhibits characteristics of a link farm, with numerous embedded URLs, many hosted on Shopify, likely for SEO manipulation to increase visibility of the malicious redirector. 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.com/pify?keyword=abstract+algebra+problems+pdf
    • http://files.smallcoffee.ca/uploads/1/3/1/3/131383434/bimenagidefa_jotoziw_pigojajisapas_sunidexogubut.pdf
    • http://files.vafercapital.com/uploads/1/3/0/7/130775867/nivej_gusakigaveg_dijerikikezade.pdf
    • http://files.leandremeldener.com/uploads/1/3/0/9/130969190/3481642.pdf
    • http://files.dianajart.com/uploads/1/3/1/4/131482878/6018816.pdf
    • https://cdn.shopify.com/s/files/1/0430/3300/2145/files/32505767549.pdf
    • https://cdn.shopify.com/s/files/1/0431/1325/0965/files/veguxe.pdf
    • https://cdn.shopify.com/s/files/1/0434/0134/7226/files/noxokamemaluvupopofekibet.pdf
    • https://cdn.shopify.com/s/files/1/0429/3469/8147/files/email_id_list.pdf
    • https://cdn.shopify.com/s/files/1/0427/7128/4135/files/online_to_word_converter_with_editing_options.pdf
    • https://cdn.shopify.com/s/files/1/0434/6452/3926/files/mozesefikedumoleg.pdf
    • https://cdn.shopify.com/s/files/1/0428/3236/3676/files/73813260005.pdf
    • https://cdn.shopify.com/s/files/1/0428/5035/3318/files/51139582287.pdf
    • https://cdn.shopify.com/s/files/1/0433/3341/9160/files/asturias_guitar_free.pdf
    • https://cdn.shopify.com/s/files/1/0428/6421/4182/files/metro_lisboa_mapa.pdf
    • https://cdn.shopify.com/s/files/1/0436/8223/4521/files/sql_lookup_table.pdf
    • https://cdn.shopify.com/s/files/1/0437/1821/3797/files/gomelofogoxuwop.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_off0000643f.bin
0c801e1a4ee8e6616cd4f084c9e3a74462dc6e2da81e57ff3433e5077b099112
pdf-font-stream PDF embedded font (sfnt) at offset 0x643F 5604 bytes
font_01_sfnt_off00007733.bin
fb9907b4b8ea771cbc9298443819fec8cf46e7540faf6fad4e795fd39bba3bd5
pdf-font-stream PDF embedded font (sfnt) at offset 0x7733 10080 bytes