Malicious PDF — malware analysis report

Static analysis result for SHA-256 3d11aaab70071c48…

MALICIOUS

PDF

39.8 KB Created: 2020-08-22 13:17:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 18a8178a7ce270db5c05b726e8dae140 SHA-1: b9b1dc69d620a9f91aaa21400440b95010ec2604 SHA-256: 3d11aaab70071c487edd232fbf1f3039ea2c3d85d6a14414d3914988013adc4d
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell T1204.002 Malicious Link

The PDF contains a large number of embedded links, many of which point to a link farm hosted on Shopify. One critical heuristic identified a link to a known malicious redirector, ttraff.cc, which is used to obscure the final destination. The document body also contains the URL for this redirector, suggesting a lure to trick users into clicking on what appears to be exam answers. The ML classifier strongly flagged this PDF as malicious.

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/pify?keyword=autodesk+inventor+certified+user+exam+imperial+answers
    • http://damuwuf.tmeansphotography.com/uploads/1/3/0/7/130740514/5046371.pdf
    • http://files.thesilkfamilyproject.com/uploads/1/3/1/4/131437740/livig.pdf
    • http://files.millyverchar.com/uploads/1/3/2/8/132814096/xugiwut-wusijonuko-mozezupad.pdf
    • http://vukajegix.hersheyblazetc.org/uploads/1/3/1/6/131606739/sovawofovufukareke.pdf
    • https://cdn.shopify.com/s/files/1/0431/6397/5835/files/2142314682.pdf
    • https://cdn.shopify.com/s/files/1/0428/5032/0540/files/nibosejir.pdf
    • https://cdn.shopify.com/s/files/1/0431/1669/1612/files/pravastatina_dosis.pdf
    • https://cdn.shopify.com/s/files/1/0437/8486/3893/files/xitabisozolagalasel.pdf
    • https://cdn.shopify.com/s/files/1/0429/0982/7231/files/zeditekalanot.pdf
    • https://cdn.shopify.com/s/files/1/0430/0305/2191/files/rockwood_pop_up_camper.pdf
    • https://cdn.shopify.com/s/files/1/0431/0119/2352/files/dubefep.pdf
    • https://cdn.shopify.com/s/files/1/0434/5338/2822/files/big_love_guitar_tab.pdf
    • https://cdn.shopify.com/s/files/1/0427/5693/1751/files/52613915943.pdf
    • https://cdn.shopify.com/s/files/1/0437/7047/8746/files/gopevejikiz.pdf
    • https://cdn.shopify.com/s/files/1/0430/8742/9781/files/neurofibromatosis_adalah.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_off00005c90.bin
dcefd1fb645a5eb85150638ded8a17444c9ddec02828f68b78319373f5f5492c
pdf-font-stream PDF embedded font (sfnt) at offset 0x5C90 5572 bytes
font_01_sfnt_off00006f87.bin
7a83b4c87c2e889b527d0549892e4fce9cae217c6d8084cde415979da825bc0d
pdf-font-stream PDF embedded font (sfnt) at offset 0x6F87 10068 bytes