Malicious PDF — malware analysis report

Static analysis result for SHA-256 45fbc52515e7f516…

MALICIOUS

PDF

49.3 KB Created: 2020-08-19 18:18:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d9b64bede31f14f2f6024f9133a35363 SHA-1: ba9e9279f402c67d383f5a325bf5ee293187fc65 SHA-256: 45fbc52515e7f516cfdc1378fe283e11a36b3e0207b9fe06ab1083cf4d72e2e8
152 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many of which point to a link farm hosted on Shopify, but one critical link directs to a known malicious redirector. The document body, though heavily obfuscated, contains text related to 'Tombow dual brush pen lettering practice sheets' and the malicious URL, suggesting a lure to a phishing or malware distribution site. 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=tombow+dual+brush+pen+lettering+practice+sheets
    • http://gerif.aphrodites-boudoir.com/uploads/1/3/1/8/131857101/pigojurunojovujekur.pdf
    • https://cdn.shopify.com/s/files/1/0433/5848/6678/files/service_manual_torrent.pdf
    • https://cdn.shopify.com/s/files/1/0437/2961/7057/files/tunepagoligiwenilijuz.pdf
    • https://cdn.shopify.com/s/files/1/0434/7484/5858/files/ansys_fluent_18._1_tutorial.pdf
    • https://cdn.shopify.com/s/files/1/0431/2471/9773/files/54189327445.pdf
    • https://cdn.shopify.com/s/files/1/0434/0894/9402/files/1._7._10_pvp_servers.pdf
    • https://cdn.shopify.com/s/files/1/0430/2965/9797/files/dinewulejuregoborepe.pdf
    • https://cdn.shopify.com/s/files/1/0440/9648/7576/files/lakewami.pdf
    • https://cdn.shopify.com/s/files/1/0429/7680/5023/files/buriligif.pdf
    • https://cdn.shopify.com/s/files/1/0435/5578/2817/files/nutritional_information_canned_chopped_tomatoes.pdf
    • https://cdn.shopify.com/s/files/1/0436/2010/6404/files/18_wheel_of_steel_haulin_mods.pdf
    • https://cdn.shopify.com/s/files/1/0437/3587/5745/files/52001727874.pdf
    • https://cdn.shopify.com/s/files/1/0433/9856/1959/files/learn_small_english_sentences_with_tamil_meaning.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00006bcf.bin
b722ac7096095700e20b9364417f800d9a3a8874bf77333f56167cf31f3b8ac3
pdf-font-stream PDF embedded font (sfnt) at offset 0x6BCF 5668 bytes
font_01_sfnt_off00007f05.bin
78d37ac8ca89ff989e3576c813c12209908bf9ef81a029edca986e627290cd53
pdf-font-stream PDF embedded font (sfnt) at offset 0x7F05 10304 bytes
font_02_sfnt_off0000a27a.bin
d4c4feb8951055c2fa9bcdd55af7a36c85e906000362d0091f30ac23a55c13ed
pdf-font-stream PDF embedded font (sfnt) at offset 0xA27A 16192 bytes