Malicious PDF — malware analysis report

Static analysis result for SHA-256 21a1cfd5224488c9…

MALICIOUS

PDF

49.6 KB Created: 2020-08-31 00:05:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 16314e092703d9476f38d7917f9fc7a9 SHA-1: 3886a32caa3a779e6a806348a712a26e7155f09a SHA-256: 21a1cfd5224488c9fba795ff011328cf20e800de0f2cd4226e4b5aa8a5a36de1
152 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, with one specifically pointing to a known malicious redirector. The document body, though heavily obfuscated, contains text referencing 'Trinity rescue kit download' and the malicious URL. This suggests a social engineering attack aiming to trick users into visiting a malicious site.

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/wix?keyword=trinity+rescue+kit+download
    • https://cdn.shopify.com/s/files/1/0434/3011/7526/files/43090639172.pdf
    • https://cdn.shopify.com/s/files/1/0429/1746/2182/files/ygdrasil_jorge_baradit.pdf
    • https://cdn.shopify.com/s/files/1/0429/4190/7100/files/givafelufutaxejopamut.pdf
    • https://cdn.shopify.com/s/files/1/0434/3303/3877/files/capitals_of_the_world_list.pdf
    • https://cdn.shopify.com/s/files/1/0435/1872/2216/files/60077196548.pdf
    • https://cdn.shopify.com/s/files/1/0436/1905/7826/files/78756138385.pdf
    • https://cdn.shopify.com/s/files/1/0431/2399/8874/files/87196274797.pdf
    • https://cdn.shopify.com/s/files/1/0431/7108/6485/files/mefavasiwazixigasele.pdf
    • https://cdn.shopify.com/s/files/1/0436/6968/4377/files/98148527820.pdf
    • https://cdn.shopify.com/s/files/1/0430/8546/3713/files/nobabone.pdf
    • https://cdn.shopify.com/s/files/1/0461/9829/2643/files/43847186230.pdf
    • https://cdn.shopify.com/s/files/1/0430/5554/6517/files/pelarimuw.pdf
    • https://cdn.shopify.com/s/files/1/0435/1524/8794/files/calculate_time_difference_in_android_studio.pdf
    • https://cdn.shopify.com/s/files/1/0432/9521/1680/files/54591702628.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/nazowexoratusitufunu.pdf
    • https://cdn.shopify.com/s/files/1/0436/8993/5003/files/kiwewepobawiludow.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_off00007996.bin
237a052b694b03903a8b3aa5c890f36fc535ae629cf24e424370e7bf55f11785
pdf-font-stream PDF embedded font (sfnt) at offset 0x7996 5140 bytes
font_01_sfnt_off00008b39.bin
67141c8062f830b664fd30c2bb97a67ed040b267074053c14be7190a02b64fe0
pdf-font-stream PDF embedded font (sfnt) at offset 0x8B39 14856 bytes