Malicious PDF — malware analysis report

Static analysis result for SHA-256 fa9b3692c891b675…

MALICIOUS

PDF

59.0 KB Created: 2020-08-06 07:13:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 28dc4f17cdabb21f769a82179320756d SHA-1: e4172f05bee25e3bb148179fb8ad31c383330ebb SHA-256: fa9b3692c891b6753413887352a6b9f600e0c95af0df298dfcf759029c1f20ef
154 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many pointing to Shopify domains hosting other PDFs, but one critical link directs to a known malicious redirector. The document body, though heavily obfuscated, contains the text 'Brain teasers for high school pdf' and the malicious URL, suggesting a lure. The heuristic PDF_MALICIOUS_REDIRECTOR_LINK confirms the presence of a link to malicious infrastructure.

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=brain+teasers+for+high+school+pdf
    • http://files.meanevilstepteacher.com/uploads/1/3/1/3/131398605/kowilupe.pdf
    • http://files.baconandbears.com/uploads/1/3/0/9/130969435/dijut.pdf
    • http://files.aquinasphysics.com/uploads/1/3/1/6/131606807/4f1fa203bcbaed.pdf
    • https://cdn.shopify.com/s/files/1/0436/0100/2664/files/dapopedobe.pdf
    • https://cdn.shopify.com/s/files/1/0432/1568/3744/files/basis_set_superposition_error.pdf
    • https://cdn.shopify.com/s/files/1/0432/5641/4363/files/fabufopu.pdf
    • https://cdn.shopify.com/s/files/1/0429/3849/9235/files/xefewuvogig.pdf
    • https://cdn.shopify.com/s/files/1/0434/5135/1200/files/toefl_sample_tests.pdf
    • https://cdn.shopify.com/s/files/1/0432/9072/2469/files/66411756305.pdf
    • https://cdn.shopify.com/s/files/1/0430/0223/2983/files/brassage_gntique.pdf
    • https://cdn.shopify.com/s/files/1/0434/1576/5159/files/give_me_liberty_apush_textbook.pdf
    • https://cdn.shopify.com/s/files/1/0434/2353/1158/files/codex_calixtinus_download.pdf
    • https://cdn.shopify.com/s/files/1/0427/6482/8838/files/46427435322.pdf
    • https://cdn.shopify.com/s/files/1/0427/9032/2335/files/48441657224.pdf
    • https://cdn.shopify.com/s/files/1/0434/2700/4572/files/76609042731.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00009a67.bin
f5a4f54b598c5a5cf359b4d3c3b51596b478a42f59d48b01073ed392f0da13c0
pdf-font-stream PDF embedded font (sfnt) at offset 0x9A67 5256 bytes
font_01_sfnt_off0000ac38.bin
2581dc1d1a017824f92785a2f9bd7881aa1e4c66935700c7204371dbd71b8309
pdf-font-stream PDF embedded font (sfnt) at offset 0xAC38 10664 bytes
font_02_sfnt_off0000d078.bin
ff5f0ef16caf3e97cd1984b3a03ea88e11eab8cf63d2ee006085a4b9995833f3
pdf-font-stream PDF embedded font (sfnt) at offset 0xD078 4324 bytes