Malicious PDF — malware analysis report

Static analysis result for SHA-256 9b921ab4f7b3fafd…

MALICIOUS

PDF

41.4 KB Created: 2020-08-28 02:59:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 23a26b24973c890d922a3fe2887d9914 SHA-1: bf5395c01d0918b536522f10dab503d36562eb96 SHA-256: 9b921ab4f7b3fafdb10eca569ca6258ad496e1d077b1c59b1f9a6ab3ed4a9cfb
154 Risk Score

Malware Insights

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

The PDF contains embedded links, one of which points to a known malicious redirector. The document body, though heavily obfuscated, contains text related to a 'yellow belly turtle care sheet' and the malicious URL. The PDF_MALICIOUS_REDIRECTOR_LINK heuristic confirms the presence of a link to malicious infrastructure. The ML classifier also strongly indicated maliciousness.

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.ru/pify?keyword=yellow+belly+turtle+care+sheet
    • http://files.deustone.com/uploads/1/3/2/8/132815791/754743.pdf
    • https://cdn.shopify.com/s/files/1/0432/3845/7508/files/35574597839.pdf
    • https://cdn.shopify.com/s/files/1/0433/7762/3194/files/11371960457.pdf
    • https://cdn.shopify.com/s/files/1/0431/9805/4558/files/buvalamokexig.pdf
    • https://cdn.shopify.com/s/files/1/0432/3255/9267/files/33022694800.pdf
    • https://cdn.shopify.com/s/files/1/0448/6771/5234/files/amoeba_sisters_characteristics_of_life.pdf
    • https://cdn.shopify.com/s/files/1/0433/3538/5243/files/abc_writing_practice_book.pdf
    • https://cdn.shopify.com/s/files/1/0438/2618/4352/files/vewijonalejubumu.pdf
    • https://cdn.shopify.com/s/files/1/0431/4238/1725/files/tennessee_sample_ballot_2016.pdf
    • https://cdn.shopify.com/s/files/1/0451/4267/1513/files/c_m_d_ka_full_form.pdf
    • https://cdn.shopify.com/s/files/1/0435/6879/1713/files/jojixumofaxowal.pdf
    • https://cdn.shopify.com/s/files/1/0434/2022/1596/files/34863583712.pdf
    • https://cdn.shopify.com/s/files/1/0430/3529/5905/files/82576887830.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_off000063f0.bin
600bf8c7c78d8996b3cac2bb9be77b2bffdb40ecc99377347ac479e20f352526
pdf-font-stream PDF embedded font (sfnt) at offset 0x63F0 5180 bytes
font_01_sfnt_off0000759f.bin
c98523d1476c2f89ed8fc03c4e153590a8e2c7d66a9cc28fc4031f69f0d94f14
pdf-font-stream PDF embedded font (sfnt) at offset 0x759F 10228 bytes