Malicious PDF — malware analysis report

Static analysis result for SHA-256 aa3dfab0693eb929…

MALICIOUS

PDF

43.0 KB Created: 2020-07-27 13:22:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: fa582d061f074e39e9aee5519faf4ca2 SHA-1: d6129eb8a67e423227bdff44775edd100eaeb0f8 SHA-256: aa3dfab0693eb9296568b82ffa8f2160a614db430bb3fcd5aa61024ac7b03726
152 Risk Score

Malware Insights

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

The PDF contains a link to a known malicious redirector, ttraff.com, which is disguised as GCSE test papers. The ML classifier strongly indicates maliciousness. The document body, though heavily obfuscated, contains text related to 'gcse test papers with answers', reinforcing the lure. The presence of numerous external PDF links, many hosted on Shopify, suggests a link farm or SEO poisoning tactic to distribute the malicious content.

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=gcse+test+papers+with+answers
    • http://files.laducaautoservice.com/uploads/1/3/2/6/132696249/jeposajakibeg.pdf
    • http://files.aglimpseofhues.com/uploads/1/3/1/4/131438692/f634f3efd5e.pdf
    • http://files.inspiredelephant.com/uploads/1/3/2/7/132712306/5662e1ee2d8.pdf
    • http://files.shilohchristianband.com/uploads/1/3/1/4/131409861/nebuvejilep.pdf
    • http://files.laducaautoservice.com/uploads/1/3/2/6/132696249/jep
    • https://cdn.shopify.com/s/files/1/0435/1347/9320/files/40908314479.pdf
    • https://cdn.shopify.com/s/files/1/0433/3728/5797/files/foxewaxejitorigagorizu.pdf
    • https://cdn.shopify.com/s/files/1/0431/7652/5988/files/85364359245.pdf
    • https://cdn.shopify.com/s/files/1/0430/7245/4810/files/86072677293.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/71895705060.pdf
    • https://cdn.shopify.com/s/files/1/0427/4470/9276/files/37648801180.pdf
    • https://cdn.shopify.com/s/files/1/0432/7096/3350/files/80307828622.pdf
    • https://cdn.shopify.com/s/files/1/0435/4395/3563/files/xesud.pdf
    • https://cdn.shopify.com/s/files/1/0431/6699/0498/files/wonaxiliwevag.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_off00006965.bin
35a84ace872410d00b265ba81333481ed45c5118a280ef2c1cbd89ed89536576
pdf-font-stream PDF embedded font (sfnt) at offset 0x6965 4792 bytes
font_01_sfnt_off000079aa.bin
afa1c1d9a54d7bf32c1bc1a53c27abf0d7866dc5d93f2c7da3fe0eeaf92056a3
pdf-font-stream PDF embedded font (sfnt) at offset 0x79AA 10588 bytes