Malicious PDF — malware analysis report

Static analysis result for SHA-256 e31b0eaf6a543215…

MALICIOUS

PDF

46.1 KB Created: 2020-08-13 22:42:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e8c1935e2a4ce3a195e9df54fafa5843 SHA-1: 1993b0e5d144aca7ee664fa9dd2b4f63f6853ff2 SHA-256: e31b0eaf6a543215d7528e44a1d116a8a1fef439ee3c299676999bd82de50901
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell

The PDF was flagged as malicious by a machine learning classifier and contains a critical heuristic indicating a link to a known malicious redirector. The document body, though heavily obfuscated, contains the URL 'https://ttraff.cc/pify?keyword=c+format+specifiers'. This redirector is likely used to obscure the final destination, which could be a phishing page or a malware download. The presence of numerous other links, many pointing to benign Shopify URLs, suggests a link farm or SEO poisoning tactic to increase visibility.

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=c+format+specifiers
    • http://files.lynnettejessop.ca/uploads/1/3/0/9/130969312/4981998.pdf
    • http://files.kathleengibbsauthor.com/uploads/1/3/1/3/131380120/vopisoj.pdf
    • http://files.mwalkerhunter.com/uploads/1/3/1/4/131437615/7359027.pdf
    • http://xodesak.geraintrhys.com/uploads/1/3/0/7/130776485/6567774.pdf
    • https://cdn.shopify.com/s/files/1/0433/7739/3815/files/beijing_platform_for_action_1995.pdf
    • https://cdn.shopify.com/s/files/1/0433/7205/2643/files/tibialis_anterior_stretches.pdf
    • https://cdn.shopify.com/s/files/1/0430/9542/5191/files/vamiwemilileduka.pdf
    • https://cdn.shopify.com/s/files/1/0431/7102/0957/files/exotic_birds_mod.pdf
    • https://cdn.shopify.com/s/files/1/0436/0654/0445/files/math_symbols_with_names.pdf
    • https://cdn.shopify.com/s/files/1/0431/5811/0363/files/dessert_darwin_download.pdf
    • https://cdn.shopify.com/s/files/1/0433/6310/6968/files/5661858536.pdf
    • https://cdn.shopify.com/s/files/1/0432/2020/5726/files/92866843695.pdf
    • https://cdn.shopify.com/s/files/1/0428/5464/5916/files/97757506844.pdf
    • https://cdn.shopify.com/s/files/1/0427/5650/5756/files/21021717149.pdf
    • https://cdn.shopify.com/s/files/1/0429/9931/6639/files/73103425772.pdf
    • https://cdn.shopify.com/s/files/1/0430/3293/6605/files/41519856711.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_off00006c6d.bin
a89eb90ff0cc383e44bde05bf528e9a37694b900ddf2b5ef9e1ebdd7776ab214
pdf-font-stream PDF embedded font (sfnt) at offset 0x6C6D 5036 bytes
font_01_sfnt_off00007d76.bin
19d7e34abc4e6e9b04f57100cf50a1ecc9b312e5ef148c74b145fc8e406d3ad3
pdf-font-stream PDF embedded font (sfnt) at offset 0x7D76 14632 bytes