Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4815f9c4ad89e28…

MALICIOUS

PDF

36.0 KB Created: 2020-08-24 22:43:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 227cd1956fcf2dafdfc5799e9a137235 SHA-1: b02e6c8afa4742cbc22922b7f53e5d57403ec623 SHA-256: f4815f9c4ad89e2856ee88b51438a39af0f22d3026930d22cdcdd5ac94515624
154 Risk Score

Malware Insights

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

The PDF contains a significant number of embedded URLs, with a critical heuristic firing indicating a malicious redirector link. The ML classifier also strongly flagged this PDF as malicious. The document body appears to be obfuscated or corrupted, but the presence of the redirector URL suggests a phishing or SEO poisoning attack. The primary IOC is the redirector URL, which is likely used to funnel victims to malicious sites.

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.cc/pify?keyword=king+single+fitted+sheet+target
    • http://gomur.vettoriofficial.com/uploads/1/3/1/3/131398504/sewudunubukapamuz.pdf
    • http://files.stemcellwanglab.com/uploads/1/3/0/7/130775633/e1ac54b63b1.pdf
    • http://tojiw.mattwheeleronline.com/uploads/1/3/1/6/131636725/2378efc62bc3a.pdf
    • https://cdn.shopify.com/s/files/1/0429/3220/7782/files/world_map_countries_and_continents.pdf
    • https://cdn.shopify.com/s/files/1/0436/2331/7662/files/25757386029.pdf
    • https://cdn.shopify.com/s/files/1/0431/0633/6925/files/wunisutoga.pdf
    • https://cdn.shopify.com/s/files/1/0430/6790/0061/files/63813161783.pdf
    • https://cdn.shopify.com/s/files/1/0430/7881/1810/files/mukojajat.pdf
    • https://cdn.shopify.com/s/files/1/0431/1128/4893/files/vujozekisotatawigabib.pdf
    • https://cdn.shopify.com/s/files/1/0433/9132/0214/files/95331557683.pdf
    • https://cdn.shopify.com/s/files/1/0431/6489/3345/files/consumer_and_industrial_buying_behaviour.pdf
    • https://cdn.shopify.com/s/files/1/0435/7193/7439/files/edexcel_a_level_maths_textbooks_2020.pdf
    • https://cdn.shopify.com/s/files/1/0439/3825/0910/files/line_of_best_fit_matlab.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_off0000505c.bin
0040de55ed98e84db2e4532feb9bffc1a9f3fa4188810f76a421106cfa3af2ed
pdf-font-stream PDF embedded font (sfnt) at offset 0x505C 5140 bytes
font_01_sfnt_off000061cb.bin
2c0316d7af868cf80b77f1b354fc993feb02d342ebabb1b78a144fc33c14d124
pdf-font-stream PDF embedded font (sfnt) at offset 0x61CB 9860 bytes