Malicious PDF — malware analysis report

Static analysis result for SHA-256 81f4675fc7acdf9c…

MALICIOUS

PDF

42.8 KB Created: 2020-08-22 23:14:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 981fcf7ef72d6f8dce9bd19a5ade0283 SHA-1: 76091bb2ac29fcf1ed27e673dc27e5f9896caba7 SHA-256: 81f4675fc7acdf9ca2c79f0a5c49c7be308c41890f1d1690d508869f0ca594ae
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a link that redirects to a malicious domain, likely as part of a phishing or scam campaign. The document body, though heavily obfuscated, contains text related to a 'geoffrey chaucer biography worksheet' and a URL pointing to a redirector. The presence of numerous external links, many pointing to Shopify-hosted PDFs, suggests a link farm or SEO manipulation tactic to distribute malicious content. No scripts were extracted, but the PDF structure itself facilitates the malicious redirection.

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=geoffrey+chaucer+biography+worksheet
    • http://files.wisconsinwaterlaw.com/uploads/1/3/2/6/132695818/gekisakawojavitul.pdf
    • http://files.syandash.co.uk/uploads/1/3/0/8/130873876/baguf-gubiwapeb.pdf
    • http://jubuleper.creedmoorcivic.org/uploads/1/3/0/7/130775350/medubebewodovoma.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0463/2657/9362/files/android_one_mi_max_2.pdf
    • https://cdn.shopify.com/s/files/1/0440/0565/4678/files/43152591254.pdf
    • https://cdn.shopify.com/s/files/1/0436/8538/0246/files/voguvubuf.pdf
    • https://cdn.shopify.com/s/files/1/0433/4157/8399/files/jipaka.pdf
    • https://cdn.shopify.com/s/files/1/0434/0308/3928/files/90379528160.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/wuwikeg.pdf
    • https://cdn.shopify.com/s/files/1/0438/6249/1286/files/loweborodug.pdf
    • https://cdn.shopify.com/s/files/1/0428/6581/9814/files/denovabadawi.pdf
    • https://cdn.shopify.com/s/files/1/0428/9236/1887/files/93061329652.pdf
    • https://cdn.shopify.com/s/files/1/0430/9821/0461/files/vekuzitubusuvikasex.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/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000068a8.bin
d1193fe07a8f3bd07fe2bd89a70235cf4e5c4bdb8bafe08b8f00ba329feb10bc
pdf-font-stream PDF embedded font (sfnt) at offset 0x68A8 5676 bytes
font_01_sfnt_off00007c14.bin
0e060ec8fa84546f73f3aea8dfdc4adbf26291c0899420fd6a1c2bda0898fe2c
pdf-font-stream PDF embedded font (sfnt) at offset 0x7C14 10076 bytes