Malicious PDF — malware analysis report

Static analysis result for SHA-256 9fe500eae086eed6…

MALICIOUS

PDF

50.4 KB Created: 2020-08-13 18:55:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 0f144bb4c5e1a4b4cc981b047ec9ee73 SHA-1: 0652f270d597819ef1082eb33d389e126470e20e SHA-256: 9fe500eae086eed625d14c49f930be6457c98d8d3440f8ba46b157f7e4d72278
152 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many of which point to domains associated with SEO link farms. One critical heuristic identified a link to a known malicious redirector, ttraff.cc, which is disguised as a link to an English learning PDF. The ML classifier also strongly indicated maliciousness. The primary attack vector appears to be luring users into clicking malicious links under the guise of educational 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.cc/wb?keyword=learn%20how%20to%20write%20english%20for%20beginners%20pdf
    • http://jinewe.eatbutcherandvine.com/uploads/1/3/0/8/130874435/2838866.pdf
    • http://jorikigef.jamesbondbooks.co.uk/uploads/1/3/1/8/131857101/jidamawamewuzewut.pdf
    • http://sanebu.mhmontessori.org/uploads/1/3/1/4/131455328/2905021.pdf
    • http://files.aremembers.org/uploads/1/3/2/6/132695200/5ec9c14.pdf
    • https://cdn.shopify.com/s/files/1/0437/8948/4190/files/zuludokavovaw.pdf
    • https://cdn.shopify.com/s/files/1/0439/2773/2379/files/apprendre_le_japonais_pour_dbutant.pdf
    • https://cdn.shopify.com/s/files/1/0429/2821/0073/files/hcsb_apologetics_study_bible.pdf
    • https://cdn.shopify.com/s/files/1/0428/7250/4483/files/99724532075.pdf
    • https://cdn.shopify.com/s/files/1/0441/0041/9736/files/vanefuzariseduv.pdf
    • https://cdn.shopify.com/s/files/1/0432/5398/9534/files/4350384518.pdf
    • https://cdn.shopify.com/s/files/1/0429/2296/7206/files/wobagopiwabubevotev.pdf
    • https://cdn.shopify.com/s/files/1/0431/3622/1351/files/gofijomuruvozinolewuwejaj.pdf
    • https://cdn.shopify.com/s/files/1/0440/1253/5958/files/werubulajiseronarotinopi.pdf
    • https://cdn.shopify.com/s/files/1/0432/8249/7700/files/bivawajegabiboziduv.pdf
    • https://cdn.shopify.com/s/files/1/0429/5832/3865/files/91696674041.pdf
    • https://cdn.shopify.com/s/files/1/0428/8688/9625/files/24511606409.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_off00008021.bin
fdb98d1607de921653c317489d90d61cf5838b3bcb3ae310f2a1047944a88595
pdf-font-stream PDF embedded font (sfnt) at offset 0x8021 5476 bytes
font_01_sfnt_off000092c9.bin
f5375c50a2fc6834354332afcb71dd6d2e6d0c92c096c076d484944fadf4f839
pdf-font-stream PDF embedded font (sfnt) at offset 0x92C9 11736 bytes